Want to start making my own circuit board where to start - Page 1
Forum section: electronics / beginners

author: Beamin
author_rank: Super Contributor
timestamp: July 22, 2017, 08:48:04 am
content: I guess first thing is a laser printer. Anything special about it? Or can I just go with a cheap one? Also how much am I looking to spend on it?What do you print on? Staples had a box of 100 clear transparencies but they were 70 bucks! I know staples is a rip off but at that price this would be cost prohibitive.anything special about the UV light? Will a black light work? I don't like the idea of eye damage. Ferric Chloride seems to be the best chemical except for its not safe to dump down the drain but I can manage safe disposal.I also saw a youtube video where the guy prints on what looks to be a magazine page and irons it on the copper. Has anyone tried this?

author: KL27x
author_rank: Super Contributor
timestamp: July 22, 2017, 10:58:37 am
content: Plenty of people swear by UV. But it is not particularly hard to do toner transfer with very similar results. Unless you need smaller than say 7/7 traces, regularly, toner transfer can do it cheaper. And it is faster/easier in almost every respect, once you understand the entire process. It will do everything short of BGA (really can't do that with UV, either, unless you wanna plate thru holes, yourself?), although UV will perhaps have a slight edge in the minimum size of your vias.If you wanna do toner transfer, I can offer some pointers.

author: tggzzz
author_rank: Super Contributor
timestamp: July 22, 2017, 11:36:23 am
content: Quote from: Beamin on July 22, 2017, 08:48:04 amYou need to give us more information, e.g. how you will design the PCB (cf manufacturing it) acceptable turn-around time, size of components and tracks, PCB size, single/doublesided, other attributes, and how you will assemble the components on the PCB.You can read about my experiences making PCBs after a 30 year (gulp) gap at my blog; see the .sig. I wasverypleasantly surprised at how easy it is nowadays. The major techniques are:laser tonerlaser toner (works, just about OK unless you have practiced your technique)cheap Chinese PCBs (excellent, but there is a turn-around time)manhattan or dead-bug techniques over a groundplane (excellent for one-offs including medium speed digital and RF)I haven't tried UV, so I won't comment. As for solderless breadboards: just say no!

author: Rerouter
author_rank: Super Contributor
timestamp: July 22, 2017, 11:59:53 am
content: for transfers grab a glossy magazine from a freind or find a cheap one, cut it to A4 sizes, and print on that. you will want dpi set as high as you can, and toner darkness as high as it will go.Be aware that depending on how your printer interprets vector lines, it may not have seamless bends, e.g. the image attached, its 8/6 traces, but note how the 45 degree corners end up broken, its because my printer treated the segments seperatly, by going in to the printer settings and setting it to use raster images rather than vector i was able to fix it.The image in this example was printed on a hp laserjet 4000, but my days of toner transfer are over. and i use a board house to punch it out, you would likely want a laser with better than 600dpi to handle below 10/10.

author: rstofer
author_rank: Super Contributor
timestamp: July 22, 2017, 04:57:28 pm
content: I did this stuff back in the early '70s and I won't be doing it again.I haven't learned how to use one of the more complete software packages like KiCad that will generate Gerber files and allow me to see off to China - nor would I want to wait.I use ExpressPCB for everything. It doesn't have pads for BGAs but I don't know how to solder them anyway. Or, more to the point, I don't know how to inspect the solder joints.ExpressPCB has a schematic entry program linked to a board layout program. Everything is placed and routed manually, there is no automation, and it takes a while to get the layout just right. Then a little online order and the boards are in hand in about a week.I have been using ExpressPCB for about 12 years and I really like their service.I have one of the Miniboards with a dozen or so DIPs and 100 or so discretes so this is a very capable service.

author: Beamin
author_rank: Super Contributor
timestamp: July 22, 2017, 06:46:02 pm
content: For time I don't want to mail order, I want to do everything at my house. For size its mainly going to through hole or if surface mount its going to be the largest size packages I can find for analog parts. For IC's that have to be surface mount I will go with the largest size I can find, I don't like working with small things. I don't have the skill to create anything crazy: Think 555 timers and simple op amps. No crazy bga's or super fine pitch pins. Sorry I don't know the size numbers. Is the ironing a magazine tonner transfer method? Seems like a good way to simplify things.

author: KL27x
author_rank: Super Contributor
timestamp: July 22, 2017, 07:41:20 pm
content: I have done toner transfer for over a decade. It's only once every few months, but sometimes I do a lot of boards at a time.Here are the two important bits you might not find on a google search.1. paper. The Pulsar paper they now sell at Mouser and Sparkfun and all sorts of places is amaze-balls. Yes, you can use magazine paper. I've done it. Yes, you can use laser printer label backing. Yes, even regular paper works. But I'd suggest you at least buy 1 pack of this Pulsar for reference. Because it works as good or better than any of them, and it is by far the most likely to give you good results if your technique is not great. It releases easy, leaves no fuzz around the edges. BTW, magazine paper is pretty good, but it distorts a little, which is a problem only on large double-sided boards. I think it shrinks or wrinkles when exposed to high heat.2. Pre-etch. This is incredibly important. After cleaning the boards off with soap and steel wool, you still benefit (GREATLY) from dunking your blank board into your etchant for about 10 seconds. Rinse it in a bucket of water. Then let it dry (I recommend a heat gun to speed it up). Very important: Do NOT WIPE THE BOARD. There will be a layer of precipitate that is loosely adhered to the surface of the board, all over, and it is the reason why you want to do this. If you wipe the board down with a damp paper towel, you will remove all this dust. The dust gives the surface nooks and crannies for the toner to stick and to seep in, rather than flattening out and/or falling off. If I don't do a pre-etch, my traces can come out anywhere from normal to about 2.5x as fat as they're supposed to (this means bridging between pads/traces and general wavi/uneven-ness). And they are more prone to falling off. With a good preetch, you really can't mess up.As far as the printer, I know firsthand that Brother printers which take the TN350 cartridge will not work. Most any laser printer other than those will more than likely work. Including other Brother printers.If you want to make it easy on yourself, you can buy GBC Creative laminator for maybe $30. And a 1200W heat gun for another 20-30. What I do is take the case off the laminator and shoot the board with a heat gun while it's going through. The amount of heat depends on the size of the board. I have run a lot of boards, and my first laminator is still trucking. Stored outside, near a corrosive tank, ten years. The only other mod besides removing the plastic case and screwing it to a plank of wood for a base was to egg out the holes for the roller, so that a full thickness 0.064 board will fit through. Just be careful. The metal roller is juiced up, so don't feed a copper board in barefoot or with wet hands. I've gotten a tingle, before.Thickness of the copper: this is usually described in "oz". Stick with 1 oz, or even 1/2 oz pour, for the most part. These will etch much more accurately than 2oz. If you need 2 oz, just take that into consideration when you decide what pitch you can handle.If you just want to make a tiny board that probably requires some bodging, just to say you did it, and you dont' want to spend any time or money to do it right, watch Ben Heck's toner transfer video.

author: tggzzz
author_rank: Super Contributor
timestamp: July 22, 2017, 08:36:21 pm
content: Quote from: Beamin on July 22, 2017, 06:46:02 pmYou haven't indicated the essential benefit from limiting yourself to doing everything at home.BGAs are relatively difficult to inspect and rework; I'd avoid them.Apart from that, anything down to 0603 and 0.5mm pitch can beassembledeasily by hand with limited equipment.If you only use toner transfer, I think you are limiting your options.

author: Zero999
author_rank: Super Contributor
timestamp: July 22, 2017, 09:27:42 pm
content: I've done toner transfer before but it can be a pain and lots of experimentation is required to get it right.The photographic process is the way to go, in my opinion. You can buy plain copper clad board and spray it with the photoresist but I wouldn't bother, just get pre-sensitised board, as it's much easier. UVA and the shorter visible wavelengths (indigo and violet) will work best. Don't worry about eye damage. These wavelengths are safe, as long as you're sensible and don't stare into the beam. You can buy cheap LEDs with a peak wavelength of 400nm which should work quite well but I haven't tried them myself. I'd recommend a black light compact fluorescent lamp. Don't bother with incandescent lamps: they're inefficient and get hot enough to burn/melt the transparency.https://www.amazon.com/13W-CFL-Blacklight-Bulb-Vibe/dp/B01IYDSGFKhttp://www.ebay.co.uk/itm/20W-BLACKLIGHT-ULTRA-VIOLET-UV-BULB-BC-B22-BAYONET-FITTING-BLACK-LIGHT-LAMP/252742747657

author: janoc
author_rank: Super Contributor
timestamp: July 22, 2017, 09:40:01 pm
content: Quote from: Beamin on July 22, 2017, 08:48:04 amLaser is good for doing toner transfer (in fact, inkjet will not work for that at all). That's the part with the magazine paper and ironing. Search for "toner transfer" on Google, there are tons of tutorials on it.If you want to do UV photolithography, then laser printer is actuallynotthe best option. You want as opaque black as possible and cheap lasers rarely have sufficient toner coverage on larger areas. Office grade printers usually do, but unless you can find one second hand, they are not cheap. There are some tricks, like stacking two printouts to get more opaque black, but it is both more costly (you need two transparencies) and can be a royal pain in the butt to align.For doing lithography your best bet is a cheap inkjet. Or have the transparencies printed in the nearest copy shop.UV light - black light may work, depends on the wavelength. Youdo notwant a germicide/disinfection lamp (that's where the eye damage can occur). It is not necessary for this job. If you don't want to buy/build an exposer using UV tubes, look for a small UV lamp used by ladies to cure their glue-on nails. Those are sold cheaply in drugstores.Another option is to use UV LEDs. It does work surprisingly well, there are plenty of instructions on how to build one online (e.g.http://www.instructables.com/id/UV-LED-Exposure-Box/) and the UV leds are fairly cheap.However, in a pinch even sunlight works, it just takes a while.

author: janoc
author_rank: Super Contributor
timestamp: July 22, 2017, 09:43:26 pm
content: Quote from: Hero999 on July 22, 2017, 09:27:42 pmActually, the cheapest and easiest method is to use the dry film resist. You only need a cheap office laminator to laminate it on the board. Much cheaper than pre-sensitized boards and you can use any scraps or pieces of the laminate you may have laying around, not only the few sizes the distributor carries. Spraying I really don't recommend neither - messy and next to impossible to get an even layer without dust on it.

author: tautech
author_rank: Super Contributor
timestamp: July 22, 2017, 09:58:15 pm
content: Quote from: Beamin on July 22, 2017, 06:46:02 pmGood on you for wanting to give it a go.There's a bit to learn and some expenditure to get all you need.Stick to SS boards to start with. I use Paxolin rather than FR4 as it's cheaper and easier to work with.Ironing works for some but a laminator makes the process more repeatable.Glossy papers are best for release of toner to the copper but a lot depends on your printer and its settings.Then there's etchants.......start with something you can buy off the shelf until you get some experience.Just start with a tray for etching but sooner or later you might want a etching tank.....not too hard to make.Don't try anything too complex to start with, keep good wide clearances and say 1/2 mm (20 mil/thou) traces. Wider for power. Copper plane fills reduce the amount of copper that need be removed but unless you have solid prints there will likely be some porosity.Do lots of reading on the subject, start with a forum search for 'toner transfer' in the Search button not the box at top right. (it's useless). Getting the toner transfer bit sorted is the key, printer, toner, paper and the transfer process each/all have an influence on the result. Doesn't look right, scrub the transferred toner off the copper and try again.Investment in time getting a reliable/repeatable process is the key here and when you do you can knock boards out from start to etched in under and hour.

author: Zero999
author_rank: Super Contributor
timestamp: July 23, 2017, 08:01:07 am
content: Quote from: janoc on July 22, 2017, 09:40:01 pmThe problem with incomplete coverage with laser printers can also be an issue for toner transfer too. Inket isn't ideal either, as it can run and bleed, causing lines to loose their definition and be thicker than they should be. Personally, I haven't had an issue with incomplete coverage with laser printers, when using the photographic process. I've found it to be more of a problem with toner transfer.QuoteI agree with you about not using germicidal lamps. It's completely the wrong wavelength and is totally unsuitable for exposing photoresist. There's a bad tutorial on another site which recommends germicidal tubes: if you happen to come across it avoid it and any other project on that site.Tubes from insect lamps also work quite well, along with the sort used in fraudulent bank note detection lamps.Wow, a decent project on instructables: they're not many of them on that site!

author: janoc
author_rank: Super Contributor
timestamp: July 23, 2017, 12:11:41 pm
content: Quote from: Hero999 on July 23, 2017, 08:01:07 amIt likely depends a lot on the printer used. E.g. my Samsung ML-2010 is marginal. It works for toner transfer but large areas are not covered well, there is a lot of visible banding and pitting. I have to do a lot of manual "postprocessing" with a felt marker before etching and even then it could end up being crap.I have also tried to use it to make transparencies using tracing paper* and unless I have stacked at least two, it was not sufficiently opaque for the dry film resist - even covered parts were getting exposed slightly. Two stacked produced lines that were blurry in some places because of misalignment or maybe the glass I have used to compress it didn't put even pressure on the entire surface.(* You don't have to use real plastic transparencies - paper is enough, because it is mostly transparent for the UV light. Another advantage is that it warps less in the laser printer than a transparency, even those that are actually intended for lasers)On the other hand, the larger color HP LaserJet printer/scanner combo we have at the office produces shiny, very smooth and almost completely opaque black, so it is likely that that one would work very well. Will need to check which toner it uses and see whether I could get a suitable second-hand printer off eBay.Quote from: Hero999 on July 23, 2017, 08:01:07 amI have actually built a board with UV leds based on that one to test it - it works pretty well for exposing the dry film. I am definitely more comfortable playing with that than having to deal with fragile tubes and high voltage.

author: sleemanj
author_rank: Super Contributor
timestamp: July 23, 2017, 02:30:00 pm
content: Quote from: janoc on July 22, 2017, 09:43:26 pmDon't even need that, I use a clothes iron, set very low. After cleaning the pcb, spritz it with some water, remove the cover film from inside-of-curl of the dry film in the usual manner and lay it on the wet pcb, rub it down from the center outwards with a small wad of paper towel to expel the water (water makes it easy to do without bubbles and wrinkles, and you can lift it off to grab any bit of dust that got trapped before you heat it), and then use the iron to rub and heat it which will fix it to the copper. Iron must be quite cool to avoid blistering the film, 50-70 degrees (c) works well. You can also use hotair - sometimes I will just grab that instead of fishing out the iron, I have heard a hairdryer will do the job, but I don't have enough hair to own one :-) Leave pcb to cool before exposing.

author: ion
author_rank: Regular Contributor
timestamp: July 23, 2017, 03:35:00 pm
content: I've not had much luck with toner transfer - I've made a few boards but they always took several attempts to get the toner released from the paper intact.In my opinion photolithography is a far better process. UV tubes sold for insect killers work quite well for exposure.Quote from: janoc on July 23, 2017, 12:11:41 pmI also use tracing paper to print the masks on and I find the results to be really good if I use the best quality print on my inkjet. I think HP black ink is pigment based, which would help. I seem to remember using a laser printer for my first couple of attempts - the results weren't as good.Quote from: blueskull on July 23, 2017, 12:20:39 amIf you use the dry film solder mask it isn't that hard, you apply it just like the dry film resist. It just takes a bit of experimentation to get the exposure and curing times right.

author: Zero999
author_rank: Super Contributor
timestamp: July 23, 2017, 04:10:13 pm
content: Quote from: janoc on July 23, 2017, 12:11:41 pmJust for clarity's sake, you are talking about tracing paper there, rather than ordinary copier paper? I agree, tracing paper is perfect and will work with most printers better than film. I don't know about ordinary copier paper, which I'm pretty sure is opaque to UV, as it fluoresces a greenish blue, under UV, although that might still be a short enough wavelength to expose the photoresist.QuoteAnother possibility is black light LED strip, which can be cut up into pieces and stuck to the inside of a suitable enclosure. I don't know if it's more expensive per watt of UV, than using 5mm LEDs, (the SMD LEDs in the strip are more powerful than 5mm units) but it will save a lot of soldering.http://www.ebay.co.uk/itm/5M-12V-REAL-UV-Ultraviolet-Strip-Light-Tape-Light-SMD5050-LEDs-Blacklight-/192119454976

author: janoc
author_rank: Super Contributor
timestamp: July 23, 2017, 08:27:59 pm
content: Quote from: Hero999 on July 23, 2017, 04:10:13 pmYes, tracing paper, not regular copier papier.QuoteGood idea! Haven't seen those before.

author: KL27x
author_rank: Super Contributor
timestamp: July 23, 2017, 08:29:21 pm
content: QuoteI swear people make it harder than it needs to be, just so they can build a UV LED box. I don't know how cheap is UV dry film. But the cost of Pulsar is insignificant compared to the process. And while I have not done UV, it seems obvious that UV requires more space and time and effort.Once you have got it down, it doesn't take several attempts. I haven't had to redo a toner transfer in probably 4 years. Whenever Pulsar hit the market. Scores of boards. First try is the only try. I could do it with my eyes closed and be confident in the result. There is no guesswork or maybe in the process. It's very straight forward when you don't skip steps.

author: janoc
author_rank: Super Contributor
timestamp: July 23, 2017, 08:42:51 pm
content: Quote from: blueskull on July 23, 2017, 12:20:39 amNaaaw, come on. Few people if anybody does solder mask at home and people solder even large TQFPs and QFNs on home made boards, no problem. Even 0.4mm pin pitch parts are doable (done it). Yes, without solder mask it is a bit harder but hardly impossible. Just don't use huge blobs of solder and do use plenty of flux. I seriously don't care if it is messy - it is easy to clean off with a bit of alcohol and these are usually prototype boards anyway.

author: KL27x
author_rank: Super Contributor
timestamp: July 23, 2017, 08:52:26 pm
content: ^ that's what I do. Exposed copper tracks are not an issue for me. If I make some error, which is rare, I can clean off excess solder with solder wick, if it matters.If I need corrosion resistance, I clean the board after assembly with alcohol brush and blotting with paper towels. And then I paint it with silicone conformal coat.QuoteI don't agree, even with this.I have found essentially no advantage in populating a board that has proper soldermask vs nothing. Even commercial FPC don't have soldermask between IC pads. The soldermask is more properly functioning as "trace cover," to me. To prevent shorts if mishandling and to protect from corrosion. The only place it matters is where I have thermal pad to a plane. Without mask, I need to take more care to prevent a big blob. That is the biggest "issue," if you can call it that. One biggest problem, IMO, is that without the proper magnification and lighting, looking at unmasked board is harder on your eyes. Copper and components and solder blobs can all kind of blur together.

author: tautech
author_rank: Super Contributor
timestamp: July 23, 2017, 08:56:36 pm
content: Quote from: ion on July 23, 2017, 03:35:00 pmWhich indicates your TT process wasn't well enough developed.I've had that too and when I'm in a hurry and want to get the PCB etched, just soak it in water for a bit until the transfer paper becomes soggy and rub the paper away with your fingers leaving just toner on the PCB.One has to get all/any paper coating off the PCB too before going into the etching bath.

author: KL27x
author_rank: Super Contributor
timestamp: July 24, 2017, 06:05:55 am
content: Even recent article on Hackaday on toner transfer totally omits the pre-etch part which I deem just THE MOST IMPORTANT PART.http://hackaday.com/2016/09/12/take-your-pcbs-from-good-to-great-toner-transfer/"I have no idea how the Internet rumor that you should turn up your iron “as hot as possible” came about. But I do know what the result of doing so is — smeary transfers that are extremely sensitive to the amount of pressure applied. That’s the exact opposite of what we’re looking for here. Instead, the goal is to keep the toner in the glass transition, with the temperature as low as possible so that it will fuse with the copper at our roughly constant maximum pressure."I am here to tell ya's, you can't use too much heat if you do the pre-etch. The liquefied toner is absorbed into the layer of precipitate dust. There is no fine tuning. Get it hot enough, press it a bit, and there is no way to mess it up. You can't get it too hot. You can't press it too hard (although it takes very little pressure once you get the toner totally liquefied. The pre-etched board will suck up the toner like a sponge). The only top limit to the temp is when the FR-4 bubbles/burns and the copper delaminates! I also notice he adjusts spacing of his tracks so the space between them is 2 mils larger than the tracks, themselves. This is probably an adjustment he makes for the slight fattening of traces he gets, because he doesn't pre-etch the boards.I'm sure he makes great boards. If you want to make great boards, but you don't want to have to fine tune things and do hours of experimentation, it is very, very easy. Pulsar paper. Pre etch. If you are gonna remember only 2 things, make it these two things. You can get the temp so hot that a layer of toner melts into the paper underneath the dextrin. And you get trace outline on the paper and on the copper. This is wayyyy hotter than you need. And the board will still come out fine.

author: janoc
author_rank: Super Contributor
timestamp: July 24, 2017, 08:45:04 pm
content: Quote from: KL27x on July 24, 2017, 06:05:55 amYou don't need to pre-etch - scrubbing the board clean with a scouring pad and then properly degreasing it will do the same job, cleaning and roughing the surface for the toner to stick to. Pre-etching cannot harm but it is not really necessary and it saves you one messy chemical pass.I have never had issues with toner not sticking to the laminate except when I have rushed the job through the laminator and the board remained too cold for the toner to fuse properly.I haven't tried the Pulsar paper, 12-15 euro before tax for 10 sheets (Farnell or Mouser) is heck expensive for what it is! I am normally using regular paper for non critical things and for very fine stuff I am using self-adhesive vinyl. Stick a piece on a regular paper as a carrier, print on the vinyl and then laminate it on the board. The vinyl will cleanly release the toner once hot and soft. That way you won't get any paper "hairs" and much less pitting and hairline breaks in the traces so common with paper. On the other hand, the vinyl is much more prone to smearing.Dry film resist is a lot cheaper - first link I got on eBay:http://www.ebay.fr/itm/PCB-Photosensitive-Dry-Film-for-Circuit-Production-Photoresist-Sheets-30cm-x-5m-/2218498491155m roll for about 5 bucks.

author: KL27x
author_rank: Super Contributor
timestamp: July 24, 2017, 08:51:22 pm
content: QuoteNo, it doesn't. The scouring/sanding degreases the board. It might add some very little bit of surface texture. I clean/degrease the board, too. This is an unrelated step. (I have used scotchbrite in the past, but steel wool and dish soap is the fastest and easiest to me.)I'm not talking about the toner just falling off. It will also FATTEN the traces making them 2 or even 3x thicker than the original print. This will cause bridges.When I pre etch in my cupric, this does not just put little micro pits/texture on the surface of the board. It leaves a fine, porous, fragile surface. It binds the toner and prevents it from squishing out laterally. It sucks up liquid toner. This fattening/smearing issue is why this guy has spent so much time to fine tune the exact temp in his process. He is striving to get the toner just hot enough to transfer without liquefying. This is a fools errand because gauging the temp is difficult. The exact settings and time will depend on the size and thickness of the board.In my process, there is no upper limit. There is no calibration. The sky is the limit. And I can get down to 6/6 when needed. For 8/8 and higher, there is no careful temp or pressure regulation. There are no inspections and redo's. It works. Across the entire board. Every time. And it doesn't work like this without the pre-etch.Initially, it took me several months to appreciate the importance of the pre-etch. When you do board only once a month or more, you miss things. You shrug things off. Your board is maybe different size, different pitch, different everything. That must be how it always happens, you think. And beyond that, it took me8 yearsto figure out WHAT the pre etch actually does. I eventually tried to pre-etch a stack of boards in advance. Well, in storage, I found they release some dust. I wiped one of the boards off with a damp cloth... and lo and behold my traces came out all wavy and up to 2x the width in spots. (The other 7 pre-pre-etched boards were almost as good as a freshly pre-etched board). Luckily, this was a 12/12 board. And I salvaged it by scraping out the 2 or 3 bridges that resulted. With my normal routine, I do 8/8 and don't even look at the board. I don't inspect it at any stage, because I know what I'm going to see. The pre-etch leaves the surface so fine and porous that it corrodes into dust just sitting there. Even gently wiping the board with a damp paper towel will remove the effect. And it probably even leaves dust fragments in the surface of the board from the start. You cannot replicate that with a Scotchbrite.As for cost of the paper, this is nothing to me. I don't care about the upfront cost of a laminator and a laser printer. I don't care about the cost of the paper. I don't care I spent over $100.00 on my etch tank. I care about my time. Even if UV method is free, it takes more time and space and effort. I'm probably a high volume user compared to most people. I buy the pulsar 5 packs at a time. Probably spend around $100 a year. I'm not rich, yet, but this is nothing to me. The process is simple and fast. There is no darkroom, no developer, no exposure box. No chemicals to pour or mix or store. Just a laminator, a heatgun, and an etch tank that is always ready to go.

author: tautech
author_rank: Super Contributor
timestamp: July 24, 2017, 08:52:56 pm
content: Quote from: janoc on July 24, 2017, 08:45:04 pm2 passes through the laminator fixes a poor toner bond.

author: Zero999
author_rank: Super Contributor
timestamp: July 24, 2017, 09:30:16 pm
content: I've used both toner transfer and the photo process and although I may prefer the latter, I wouldn't tell a beginner to not bother with toner transfer or say that the photographic method is the only way to make PCBs.Why does it have to turn into a flame war about which process is better? This is getting pathetic!

author: KL27x
author_rank: Super Contributor
timestamp: July 24, 2017, 09:43:42 pm
content: I wouldn't want to change anyone's mind, for gosh sake. if you like UV, then do it. If you are trying to do toner transfer, at least do it right. I'm the laziness dude I know. If I could do toner transfer without doing a pre-etch, I would. I have tried every shortcut I can. The pre-etch is worth the time, period.If you could never get toner transfer to work consistently, I know you didn't experiment with pre-etch. You thought you knew better. You rationalized it such that it doesn't matter. So you wouldn't have to do it. Because shiny boards are so much prettier. (And the guy telling you to do the pre-etch is a dick and you want him to be wrong.) But my laminator been doing these gross-looking boards for 8 years and it is not any issue on the roller.If you find UV is easier faster and more consistent, it is because you failed at toner transfer. You listened to the advice of hacks. You used a clothes iron and crappy free paper because someone else said it worked for them. You skipped step which someone said is not important. You achieved mediocre results once or twice, and then you moved on to UV. You should not give advice to noobs telling them to skip vital steps.

author: Buriedcode
author_rank: Super Contributor
timestamp: July 25, 2017, 01:28:33 am
content: Whilst it seems everythign has been covered, I'll just add my advice to the OP.Unless you have LOTS of one-off, single sided, simple boards to be made, dont' bother. Places like PCBway, will do 10 medium sized boards (10x10cm?) for $5-10. You have to pay about $30 for DHL shipping, plus they will charge you another fee I suspect (at least they did in the UK) for import tax but.... that's delivered in 4 days.. However, you get 10 very nice boards, and if you're clever each one can have multiple designs on it.I did the toner transfer method for about a decade for hobby stuff (where I only needed one PCB, only a few vias, and needed ti the same day). You can get really quite impressive results, but it is tedious, somewhat messy, and takes time, even practice. Frankly, after the first few batches I got very sick of it, the worst being the drilling - broken bits from a shoddy drill press, skewed holes, general unpleasantness. The *only* advantage I saw was that I could have an idea in the morning, and by late afternoon have a working, populated PCB doing its thing. Total costs being <£5, but mostly time. Thinking about it, I still hate it.It requires quite a lot of 'stuff', not just equipment, but consumables, and the start up costs - if you dont' already own a printer, hobby drill and drill press - can be quite high. There are many threads on this, and the web is full of advice about it.My $0.02 is.. use SMT where-ever possible. Use 1206 or 0805 0-ohm resistors as jumpers, components on the backside, and connectors on the top. ALL to avoid drilling holes for components/jumpers/vias.

author: KL27x
author_rank: Super Contributor
timestamp: July 25, 2017, 02:20:14 am
content: Thats a good point. On avoiding vias.I got pretty good at making air wire pads instead of stopping to add resistors to the schematic. Just route an extra length of wire in Eagle, escape, and do the same on the other side of the obstruction. Then increase the width of the last segment on either side to make pads. The schematic doesnt need to be changed.But dont buy all SS board. Other side can be used as a powerplane. And if only 1 or 2 traces are needex, u can cut sometimes cut them physically, instead of lining up the two sides for transfer.

author: janoc
author_rank: Super Contributor
timestamp: July 25, 2017, 09:50:46 pm
content: Quote from: KL27x on July 24, 2017, 08:51:22 pmScouringdoes notdegrease the board! What it does is that it removes the top oxidized layer and roughens the surface up, so that the toner sticks better. Degreasing is a separate step, I usually swab the board with alcohol, some people use acetone for that.Quote from: KL27x on July 24, 2017, 08:51:22 pmThat I have never seen and I have made boards with 0.5mm pin pitch TQFPs like this, which is about the finest that toner transfer is reasonable usable for. That "fattening" sounds more like the toner smearing - either because of too high temperature or some shearing force (e.g. my laminator "pulls" more strongly at the ends of the roller than in the middle due to uneven pressure, so the board could twist if I am not careful).Quote from: KL27x on July 24, 2017, 08:51:22 pmThat I agree with - if the toner is liquefying, the temperature is waay too hot. The question is whether to rely on the pre-etching to keep this in check or simply turn the heat down instead. You don't need to be exact to a degree celsius here.I am using a cheap office laminator (unmodified) for this and never had this issue with Samsung toner (maybe other formulations melt at lower temps). I have to usually pass the board through 10-15 times before it is hot sufficiently that the toner actually sticks to it (it is visible on the paper, I don't have any exact method for this).I guess this is normal because the cheap laminators are usually running up to 140-150C max, the fusers in printers go up to 200 C. On the other hand, clothes iron turned up to max reaches 240C no problem, so molten toner is a real possibility.Quote from: KL27x on July 24, 2017, 08:51:22 pmYes, if you are doing 6/6 boards, ok, I will give you that. I haven't tried to go that low, my crappy 600dpi laser is marginal for 8/8 boards already.For so fine pitch boards I prefer to order them - as you said, your time is more worth it to you than the materials. In my case the aggravation of having to deal with a 6/6 board without solder mask and made using a marginal process is not worth it to me, especially as the small boards cost like $3-5 from OSHPark for 3 copies, delivered. Just have to wait two weeks for them.

author: KL27x
author_rank: Super Contributor
timestamp: July 25, 2017, 10:27:56 pm
content: If you don't use enough heat, the toner falls off. If you use too much heat, the toner will fatten/smear. This means there's a window for success.If your setup does not allow you to get TOO hot (standard laminator won't even get that hot), then your struggle is in getting the toner to stick. Particularly on large boards. You might be running the board through 5 or 6 times to get it to (hopefully) stick.I pre-etch. I blast the board with a heat gun while it goes through a laminator. I get the board HOT. I get great transfer accuracy, every time. I'm not shooting for a tight window. I'm just clearing the lower bar by a mile and a half, plus or minus a mile. I don't make a silent prayer and squint my eyes at the moment when the paper comes off. When you are doing the second side, there's too much potential wasted time to bother with maybes.If you don't have any problem with toner falling off or fattening/bridging, you can do 1000 boards in a row and have zero issues, and you can do 8/8 reliably, then you are set. I wouldn't be close without a pre-etch. But with pre-etch, I can do THAT. Yes.QuoteSorry, yeah. I scour with wet stainless steel wool and dishsoap. Then rinse. Board is degreased. And wet. So dunking it in the etch tank and the swishing it in a bucket of water only adds another half a minute. I don't think alcohol will successfully degrease the board unless it is scoured before/during, so I think of it as the same step. Else I'm not even going to scour my boards; just quick and easy wipe with alcohol. I'm pretty sure that doesn't work. There's always little pits and such where a tiny bit of grease will hide. Scouring razes the earth and removes all the hiding places. Nowhere for grease (or toner) to hide. I scour to get the board clean. I pre-etch to add the texture. Oxidization? Who cares? Plastic toner doesn't bond chemically with clean unoxidized copper any better than oxidized copper or copper compounds left by pre-etch. Remove grease, add texture. We agree there. Scouring/sanding the board doesn't hold a candle to the porous surface left by pre-etch. Show me the machining marks in paper which allows the toner to bond to it. There are none. The paper is porous on a very fine level.QuoteWhat I'm telling you is you can remove this from your toner-transfer vocabulary. Anyone who sometimes gets fattened traces, just try it. I've already tried everything out there.

author: M4trix
author_rank: Frequent Contributor
timestamp: July 25, 2017, 11:03:19 pm
content: Quote from: janoc on July 25, 2017, 09:50:46 pmWell, I'm not sure what kind of greasy and dirty boards you people are using but here I only use something similar to Scotch brite ( not a kitchen sponge ) and a lot of tap water and of course, rubber gloves. I just scrub it thoroughly and do a test with water. If the water film on the PCB surface is unbroken for at least 20-30 seconds then it's good to go. I use dry film photoresist and you guys know how this stuff is notorious when it comes to uncleaned boards. Never had problems.

author: KL27x
author_rank: Super Contributor
timestamp: July 25, 2017, 11:13:37 pm
content: I agree, scouring > alcohol. I don't use alcohol. Scouring is the most important part of removing the grease. You're removing entire surface, all little pits/cracks which have sucked in grease. But why not add a drop of soap, while you're at it? It will prevent any bit of grease from readhering to the fresh surface you are making. Grease from your own fingers, even. (I dont wear gloves at any point, personally. I d9nt need to)@janoc, I agree. There could be lots of things "wrong" with the way I do toner transfer. From my laminator, my temps, and whatever else. But the fact that the pre-etch allows me to ignore these "mistakes" is pretty strong evidence that IT IS DOING SOMETHING. Something potentially very useful to everyone doing toner transfer. You may have just the right setup to work for you consistently. At least with one size of board. Other people, including the guy who wrote the article for Hackaday, find that they need to calibrate the temp very carefully to get consistent results, because of fattening of the toner traces/pads. They may like to learn what the pre-etch does. Scouring and degreasing the board does not do the same thing. Because you don't run into an issue doesn't mean it doesn't exist. It doesn't mean your method is wrong. It doesn't mean my method is wrong. But you're wrong if you think they do the same thing. The pre-etch GREATLY increases margin for error. If you use regular laminator without additional heat, you barely have enough to make the process work, at all. I wonder if you ever try to make a larger board or with thicker pour if you will have problems.Quote@Janoc, BTW, this is so weird to me you use vinyl method for higher accuracy. Is self-sticking vinyl that cheap? Or do you reuse it, over and over? Pulsar doesn't have any of the problems you described. As for smearing with the vinyl, maybe you can increase your accuracy with pre-etching. This also holds the toner better if you are the penny pincher using magazine/photo paper. It will be much harder to accidentally rub the toner away when you're removing the paper fibers from your board with the toothbrush. If vinyl might smear, but it leaves no fibers and releases like magic (or like pulsar?), seems like I would be using IT for the simple, large pitch stuff. Going back to my earlier years, I used to just do 4 of every board to make up for errors. Nowadays, one will do fine.

author: M4trix
author_rank: Frequent Contributor
timestamp: July 26, 2017, 12:55:41 am
content: Quote from: KL27x on July 25, 2017, 11:13:37 pmI once tried with this Arf scouring cream and it was awful. Instead of washing it leaves a strange greasy film !So, after some trials and errors, I found that just plain tap water and this 'scotch brite' ( it's more abrasive than scotch brite ) is the best solution. Regarding gloves...if I don't wear them, then my OCD kicks in.

author: tggzzz
author_rank: Super Contributor
timestamp: July 26, 2017, 05:34:59 am
content: Quote from: KL27x on July 25, 2017, 10:27:56 pmDo both sides simultaneously.Put a some fiducial 1mm holes on the board near opposite corners. Drill them. Put paper on both sides of the board, lining the fiducial holes up with the pre-drilled holes. Then use whatever technique you prefer to transfer the toner.

author: janoc
author_rank: Super Contributor
timestamp: July 26, 2017, 08:11:37 am
content: Quote from: M4trix on July 25, 2017, 11:03:19 pmI am only wiping it with alcohol after scouring to remove any accidental fingerprints from my clumsy fingers just before transfering the toner. If you are using gloves/are less clumsy than me, then this may not be really necessary.

author: janoc
author_rank: Super Contributor
timestamp: July 26, 2017, 09:05:48 am
content: Quote from: KL27x on July 25, 2017, 11:13:37 pmAs I wrote to someone else already, the alcohol/acetone isn't really absolutely necessary - I am using it only just before transferring the toner to get rid of any potential fingerprints that could have gotten on the surface after the scouring/washing. If you are using gloves or are just careful, there is no need for it. I prefer to do it to be sure, it takes 10 seconds and I am sure the board is good to go.Quote from: KL27x on July 25, 2017, 11:13:37 pmWell, it does work for a lot of people without pre-etching. All I am saying is that it might not be necessary to do it (saves a messy etching step). If it works for you and improves your yield, more power to you. The pre-etched surface is certainly more "porous" than just scoured one.Re laminator - I think you are right on that one. I didn't modify mine yet, mostly because of laziness. After a while it gets hot enough to allow the transfer, using normal 1.6mm FR4 (thicker likely won't fit between the rollers anyway), so I didn't bother with hacking it. The multiple passes are mostly required to get the board up to temperature, because only a little heat gets on the board during the 10 seconds or so that it takes for it move through the rollers.I made boards of up to 100x80mm with it, with fairly large pours and it worked - the largest problem was the pitting and banding in the pour areas from the poor coverage of my laser, not really the laminator once it got hot enough. Where my laminator tends to suck are the edges and corners of the board because it doesn't heat/press uniformly over the entire board. So I either have rotate the board between passes (risking smearing) or design around it, keeping important stuff away from the edges/corners.I may still try to open it and tweak the thermostat inside, it is the basic bimetal type, so it shouldn't be too hard to get it to a bit higher temperature.Quote from: KL27x on July 25, 2017, 11:13:37 pmThe roll of vinyl I am using costs about 15 EUR or so, definitely less that 20 EUR (don't recall exactly, it has been a long time since I have bought it). It is the kind used for decorating, kinda like self-adhesive wallpaper. I am calling it vinyl but maybe it is something else (perhaps some form of PVC?) - it is a smooth, shiny plastic on a paper carrier that you peel off when you want to stick it on something. Mine has a German vendor logo on the back, I think it is from d-c-fix (https://www.d-c-fix.com/). I am using a plain white one for the PCB work, but you could likely use any color/pattern.I am not reusing it - maybe one could do that, but it is rarely worth the trouble, with it being wet, potentially stretched from the water and lamination, etc. I just cut a piece of it slightly larger than my board, stick it on a regular paper as a carrier (that's where the self-adhesive part comes handy) and print on it. Then I cut it out and do the transfer. And then I toss it.The difference vs Pulsar is that I can get this from a self-improvement store around the corner whenever I need it. The Pulsar/toner transfer paper I would have to order by mail, which adds another 10 bucks minimum for shipping - and I get 10 A4 sheets in one pack. The vinyl roll is 5 meters x 50cm or so, for the same price.Quote from: KL27x on July 25, 2017, 11:13:37 pmVinyl is definitely easier to smear because the toner doesn't stick to it so well. It also doesn't like high temperatures - if it gets too soft too fast (before the toner fuses to the board) or, worse, starts melting, you are screwed. It needs to be just soft enough to release the toner.However, it certainly leaves no fibers (which has been my major peeve with paper - who doesn't love hairline shorts caused by these!). And when it transfers, it transfers super cleanly - there is rarely even a trace of toner left on it, everything is on the board. That may not be as important if you have a good coverage from your laser and higher resolution, but with my crappy 600dpi Samsung I need every grain of toner I can get. Furthermore, you don't need to rub it to dissolve it like the paper - I just get water between the board and the vinyl and carefully peel it off. Much faster and cleaner.I may try the pre-etching with it next time, though - if it reduces the smearing chances, great.BTW, there is also this cold transfer method for toner transfer:I haven't tried this myself, though.

author: Beamin
author_rank: Super Contributor
timestamp: August 05, 2017, 03:04:46 pm
content: So this is what I have on hand:Ink jet printersBlacklightdecent Laminator machine.(does it het hot enough without modification?)3% H2O233% Conc. HCl (I have a few gallons)I would need to buy regardless of method:1oz coper boardEtchant (or could I just use the HCl/H2O2 with any method?)So if I go UV I can use the black light and tracing paper to print on from the ink jet? The most expensive part seems to invest in a laser printer and I don't have a lot of space. So I would need to buy some type of photo resist? Wouldn't that wet and cause problems with the paper?If I go tonner transfer I would need magazine or Pulsar paper (I'm guessing you can get that in the US). Then laminate on. Put on HCl, drill and be good to go? That seems really easy. I don't have to do anything super fine and like to work with through hole parts.As far as software goes are their free programs? I could use MS paint maybe, but I could see how that would become difficult.The reason why I want to do it at home is because I want to make simple RF circuits that don't work on a bread board and there is ALOT of trial and error and I don't want to wait around for things to come in the mail especially when I might just need to add part or do reorientation. Also I can't see making more then one board since I'm not selling or producing anything.

author: janoc
author_rank: Super Contributor
timestamp: August 05, 2017, 08:01:15 pm
content: Quote from: Beamin on August 05, 2017, 03:04:46 pmForget about that acid/peroxide combo, it is cheap, but the results are fairly terrible and the acid fumes will corrode everything in range. Also you will need a ton of that peroxide - 3% is very weak, that's essentially just water that is diluting the acid. Order some ferric chloride instead.Quote from: Beamin on August 05, 2017, 03:04:46 pmYou can buy an used office laser printer for less $100, no problem. Most are built like tanks and will last you a long time. If you want to do UV instead, you can use inkjet and either use presensitized boards ($$$) or buy the dry film resist that you laminate on regular copperclad. Don't bother with the resist sprays, those are pretty much useless because unless you have a lot of practice and a dust-free room to spray it and then dry it you won't be able to obtain good results.The resist doesn't "wet", not sure what do you mean by that.Also don't forget to buy a developer for the UV resist - the type depends on what resist you are using, the presensitized boards typically use a different developer than the dry film resist.While at it, you may also want to get a drill stand for drilling the boards and some 0.8mm (or whatever is that in imperial sizes) drills - don't cheap out on that, if you try to drill the boards with a Dremel (or the wobbly piece of plastic crap they sell as a drill stand for it), you will quickly hate the job. I have one of the Proxxon Micromot tools and stands, works great.Quote from: Beamin on August 05, 2017, 03:04:46 pmToner transfer process is well documented online, you can find a ton of videos showing how to do it.Just don't use HCl + peroxide, for your own sake. It is a crappy etchant that will give you poor results because of undercutting. Also unless you have a bit of experience with chemistry and handling chemicals, you could seriously hurt yourself or at least make a nasty mess. For example, if you by mistake pour acid in the etching tray first and then add peroxide, you are asking for nasty splashes of concentrated acid in your face (you are wearing safety goggles, right?) due to the violently exothermic reaction the dilution of the acid produces.Ferric chloride is outright tame compared to that, even though the etching could take you 30 minutes instead of 5 if you don't have a bubbling tank and/or some other more fancy gear.Quote from: Beamin on August 05, 2017, 03:04:46 pmThere is plenty - Kicad is totally free (as in freedom and beer), Eagle has a free as in beer version, there is Diptrace, probably few others. Depends on what you want to do with it, each has its pros and cons. You certainly *could* use MS Paint, but that is some serious masochism.If you only need a quick and dirty board for a few simple components, drawing the tracks by hand using a permanent market/sharpie works a treat too. Just make sure to use a fresh one, so that there is enough of the paint on the board to act as resist. Then etch/drill as normal.

author: tautech
author_rank: Super Contributor
timestamp: August 05, 2017, 09:12:19 pm
content: Have a read of the OT discussion in this thread to see how others etch PCB's:https://www.eevblog.com/forum/projects/pcb-milling-failure/msg1268256/#msg1268256And following pages.

author: sleemanj
author_rank: Super Contributor
timestamp: August 06, 2017, 12:34:22 am
content: Quote from: janoc on August 05, 2017, 08:01:15 pmTosh.HCL+H2O2 works fineIt's not some massive dangerous thing, wear gloves and goggles and preferably work outdoors, as you should with Ferric Chloride too.If you are generating copious fumes or having a reaction more than small bubbles forming at the surface of the copper being etched you are doing it wrong, acid should be dilute to below fuming, add peroxide a tiny amount at a time until the etching is working at a controlled rateKeep it in a suitable capped bottle, in your garden shed/garage, not in your officeIf you spill some, neutralise, dilute, and wipe up, you won't have to deal with ferric chloride stains on everythingA laser printer can be had for a few dollars used, if you spend a hundred dollars on a used laser you are doing it wrongDry film developer can be purchased at every supermarket on the planet (sodium carbonate, either straight, or as a constituent of various laundry powders)

author: KL27x
author_rank: Super Contributor
timestamp: August 06, 2017, 01:53:34 am
content: QuoteIn the US, you can buy Pulsar through Digikey. You can find it just by putting "pulsar paper" in the product search bar.As far as the laminator goes, possibly yes, possibly no. There's plenty info in the thread and you can believe what you like. You can start a flame war / popularity contest, but ultimately you have to decide for yourself what is good enough vs what could use some improvement.Etchant has been covered, as well. Tons of people use HCl and peroxide. It is a convenient etchant, especially if you can buy 30% peroxide. Even with 3% peroxide it's easy to make but harder to reuse. Board manufacturers use all kind of etchants other than this, but you're not a board manufacturer.If you live in Europe you might be able to buy pcb tack pins much cheaper. The ones I have are made byArrowerr, maybe it's Harwin Electrronics, rather. (I threw out the box and am going by memory; yikes!) And apparently they are imported from Europe. Cost me a shiny penny, but you get a lot of them. They look like this:https://electronics.stackexchange.com/questions/192388/via-connection-pinsIf you can handle the min size of via, these are faster to stick and break off than stringing wire through your pcb. You just have to get the drill size right, so they stick and stay in until you solder them. I want to say they need a 64 gauge hole.OP: When I started doing this, everything you just said about toner transfer was good enough, at a minimum, to work most of the time. I did large traces with large clearances and I learned to make 4 of any board to make up for defects. I started out with Paint, even. You may find this good enough, at your stage in the game, too. Over the years, you might learn how to do this much better and easier and how to save yourself a lot of time and trouble. Which you will have to do for yourself, since you can't believe what you read, and the internet is actively trying to make you dumber.

author: oldway
author_rank: Super Contributor
timestamp: August 06, 2017, 07:18:12 am
content: I never had success with toner transfer.To go cheap for the production of UV's, I use a 400W Phillips tanning lamp purchased in a flea market for 5 euros.Leave a distance of about 50cm between the lamp and the printed circuit board.Exposure time 2 to 3 minutes.I install the lamp lying on the floor between 2 chairs, I place a glass plate between the two chairs and the circuit board on the glass.Put a book on the circuit board to apply pressure.

author: Buriedcode
author_rank: Super Contributor
timestamp: August 06, 2017, 07:14:23 pm
content: I think this link should be in every DIY PCB thread:http://www.electricstuff.co.uk/pcbs.htmlAlthough its old, the information is still relevant for almost every aspect of DIY PCB's. Not brown-nosing here but mike really knows his stuff, and gives practical advice.I fell into the trap that so many do, and that's trying to perfect ones technique by buying more equipment, better drill bits, a laminator etc.. it becomes more expensive than getting them professionally made, and you still have restrictions on trace width, hole sizes, no solder mask (dont' bother with DIY solder mask, its a ball-ache).

author: KL27x
author_rank: Super Contributor
timestamp: August 07, 2017, 12:46:49 am
content: QuoteI have tried it this way, and it didn't stick for me. I tend to drill 2 or 4 holes in the transfer papers to make pinholes, and then transfer 1 side. And then I center punch the board using the holes as the guide, and drill thru with tiny gauge drill bit. So my first side is technically more accurate/precise with no chance of shifting when stuffed thru the laminator and no need of tape. I'm only dealing with that with the other side. With UV it maybe doesn't matter, but another issue is using tape to fix transfer paper can make local areas of failed transfer next to the tape, so to ensure good transfer, you should remove the tape and run it again after it's been stuck.I concede this is personal preference. But in either case it takes time to do the drilling and lining. And a failure of any kind in the transfer is wasting this time. With pre-etch and what would be considered excessive heat to the un-initiated, success is automatic. You can put more time and effort into lining up the board, because you know it will not be wasted. There's only one outcome.I do some very thin boards, SS 0.007, which physically curl at a pretty tight radius. It may be of interest to others that if I do not pre-etch the board, "too much" heat is very noticeable. Aside from fattening the traces, the paper will physically separate from the board as it comes out the other side of the laminator, because the toner is liquid and it just "breaks" into two parts. One on the paper and one horrible smear on the pcb.* With the pre-etch, this will not occur even if I heat the board to the point where the FR4 starts to bubble**... i.e., using much more heat that it takes to terribly ruin a non-pre-etched board. The surface of the etched copper sucks up the liquid toner and the traces do not fatten and the paper clings to the curly board for dear life. The effect of pre-etch is night and day, and the resolution is not noticeably degraded even at insane temp. I know I use "too much heat." This is my process.*I notice the paper side is still fine. It is not fattened or distorted. The unetched copper side is what turns to a mess. If you pre-etch the copper with ferric/cupric, neither side can smear or distort. I don't know what happens with other etchants.**At this level of overcook, some fattening may be noticeable. But 10/10 all day. If doing 8/8, you will want to take a wee bit more care for accuracy sake (as well as physical damage to the board).

author: Beamin
author_rank: Super Contributor
timestamp: August 07, 2017, 02:40:37 am
content: I work with HCl and H2O all the time I aware of how it ruins all the metal in the room you are using it.So right now I could etch a board two ways:Masking tape a board cut out traces with a pin the HCl it.Take a dark sharpie make traces and HCL it. Then use alcohol to et off the ink since HCL and H2O2 wont hurt it.Correct?Whats looking the best right now is buying the film you stick to the board. Putting a thin ink jet printed paper mask over it, Black light for a few minutes, HCl for a few minutes and clean! And I only have to buy one part: the film. Simple!!

author: KL27x
author_rank: Super Contributor
timestamp: August 07, 2017, 03:37:22 am
content: I've done Sharpie, and it barely works, at best. I have tried some highly regarded pens, including Lumicolor and even compared all the different colors. I've tried baking the ink after drawing. On clean and etched copper.Even the best results I have gotten are not that great. For 1/2 oz board it works pretty well. But 1 oz, the ink can just barely hold on by the time the etch is nearing completion. I gave up even trying to do spot repairs on a bad transfer. Sometimes they work halfway, sometimes they don't do anything. I still have some boards done completely in Sharpie, and it can be made to work, but there's hardly any room for error. (More like you have to live with some error and hope it's good enough.) There are surely better pens out there, but Sharpie, Industrial Sharpie, and Lumicolor aren't that great to me, using ferric/cupric etchant. I'm not positive, but I feel like HCl and peroxide is probably even more challenging with these types of pen resists.Re UV, don't forget you have to develop the resist after you expose it. This washes away the exposed (or unexposed, depending on type of resist) areas so that the HCl can etch it. Also you have to scrub the copper clad clean and put the film on (with a laminator?).

author: Rerouter
author_rank: Super Contributor
timestamp: August 12, 2017, 12:29:06 am
content: for sharpie, you need to let it dry very well before you try and etch with it, if there is any solvent left, it will float right off the board, and will leave you cursing.Fine point felt tip pens i have found the best for this stuff, but you really will burn through a pen per board if your doing anything bigger than 5x5cm, as you need the coating to be quite thick.

author: janoc
author_rank: Super Contributor
timestamp: August 12, 2017, 08:57:42 am
content: Quote from: Rerouter on August 12, 2017, 12:29:06 amWell, as I have said, it is for quick and dirty stuff where accuracy and resolution are not a problem.I used to make circuit boards using a drafting pen filled with alcohol-soluble paint as well. That works much better than a sharpie or a felt tip pen but it is a bit more messy because of the inevitable paint stains. However, that was last time some 20 years ago when cheap lasers were not available and most diy stuff was through-hole only.

author: EPTech
author_rank: Regular Contributor
timestamp: August 12, 2017, 12:05:56 pm
content: Do not get me wrong. This is a friendly advice from a guy who (looking back and in his own opinion) wasted his time doing what you are about to do.Find yourself an online PCB prototype manufacturer and invest the time you would need to get the process fine tuned into your electronics knowledge and design. I have been there and for the money you spend on descent equipment and consumables you can easily get 5 different PCB's professionally manufactured for you.Happy prototyping.

author: sasa
author_rank: Regular Contributor
timestamp: August 12, 2017, 03:38:06 pm
content: Beamin,With laser printer instead (minimum 600DPI, better 1200DPI), results can be quite decent even with plain iron. After "mastering" the process on several boards, with Toner Transfer method, it is possible to make even 0.3mm tick trace (yes, 3/10mm, it is not the error) for single side boards (probably double-sided as well, personally never tried to made any, even after decade I do homemade PCBs). I have attached some latest boards for TQFP32 and TQFP100 (trace is around 0.3mm, space only 0.2mm).

author: Beamin
author_rank: Super Contributor
timestamp: August 14, 2017, 09:29:27 pm
content: Quote from: sasa on August 12, 2017, 03:38:06 pmSo you have a laser printer at 1200 dpi then what do you print the pattern on? Then do you take an iron to it or do you put it through a laminator?I like HCl because there's no toxic waste. But are there some methods this won't work with?This thread has left me with more questions then answers. I still don't want to order them due to the mismatch of long lead time to a short attention span and my constant need to tinker with RF stuff I will never fully understand. I could see myself trying out 10+ board for a simple FM transmitter each one spawned off the last trial. That could take a day of diy or a few months of mail order.

author: Beamin
author_rank: Super Contributor
timestamp: August 14, 2017, 09:45:35 pm
content: What do you guys think of this deal?https://www.jameco.com/webapp/wcs/stores/servlet/ProductDisplay?langId=-1&productId=2113244&catalogId=10001&storeId=10001&krypto=9x3mj8umRTpahTsnAiwyN18R8EJaby4S0PCFBoQWKMBzDrMPYTRmLsRcOFW13lVZjJOu6I2ftaNp%0D%0A438add3HkOFtx141x%2F4K&ddkey=https:StoreCatalogDrillDownViewWhat I like is no need for laminator or laser printer. The article say inkjet works just as well:http://makezine.com/2010/02/16/circuit-skills-circuit-board-etchin/Is $50 a rip off or is that fair?EDIT: That only comes with two boards. Not worth it. Probably best to buy the chemicals separately.

author: Beamin
author_rank: Super Contributor
timestamp: August 14, 2017, 10:06:45 pm
content: Another idea with ink jet:

author: sasa
author_rank: Regular Contributor
timestamp: August 15, 2017, 05:46:06 am
content: Quote from: Beamin on August 14, 2017, 09:29:27 pmYes, 1200 dpi laser printer, even I almost always print in 600dpi, except for upper 0.3mm tick traces boards.I use glossy paper from any quality paper magazine with 70 or 80g paper (some old computer magazines). Specially designed Press&Peel paper for toner transfer method is extremely expensive. Using laminator with temp. control is much better, however I use plain iron over cut-off old cotton shirt... No special equipment is needed to homemade quality board.All in all, the whole process after printing will last 45 minutes or so (25 for etching, 10 for soaking and rest for pealing off and inspection before and after etching). In the same time may be etched multiple small boards, without any specific effort, except inspection.I may write exact process step by step with exact timings in order to make down to 0.3mm traces, if that can be beneficial for you.

author: KL27x
author_rank: Super Contributor
timestamp: August 15, 2017, 06:08:03 am
content: QuoteI've had many boards made by overseas manufacturers. Thousands of dollars. This is obviously the way to go for any kind of volume order or even for one-off of a finished product of any complexity.The reason I do toner transfer is because for every one of those boards, I have several times as many one-off simple boards for prototyping or whatnot. Oftentimes the board may be just a part of the whole circuit which I am working on and perhaps for testing of an IC, some components, and/or a microcontroller I am not familiar with. It is often helpful for me to do actual testing with the device before I am ready to commit to a complete schematic/pcb/firmware, only to find out I made false assumptions or other stupid mistake when reading the datasheet, or that the theory was easier than the practice. And it's not the cost of the PCB I care about, it's all the time and effort I spent potentially going in a bad direction. All those traces I will be ripping up and rerouting. All the code I will be deleting.QuoteThis is the part I don't get. Why anyone care about the cost of the paper? I use Pulsar, and it costs about $12.00 per 10x A4 sheets. That is 1.20 per sheet, and you can get 6x 4"x3" boards from a single sheet. That is 20 cents per 4"x3" board. I don't care if magazine paper or even photoresist is FREE. If I'm doing a large number of a board, I will be submitting my Gerber to a manufacturer, which costs even MORE.It's crazy adding up pennies for process which takes perhaps 30min to several hours to design the schematic/gerber/firmware, and another 30 minutes to make the PCB, and another 30 min to populate it. And after all that, it might just go in the garbage can when you find out how bad you messed it all up.And you're talking about saving 20 cents. I spent $30.00 just in shipping charges from Mouser on my most recent project. Think of it that way; if you make 30 of your toner transfer boards with free paper, and you can save ONE 7.50 shipping charge from Mouser, lol. Step aside China. Americans are ready to work for 1/3 of your minimum wage.If you want to "save" anything significant, you have to be making a lot of boards. You might think, hey, one day I might need to make a lot of boards. And if it takes me 45 minutes to make 1 board, I can make 100 of them in 46 minutes. You will find out why the Chinese manufacturers charge you more than 20 cent a board, very quickly.10 minutes for peeling off the paper and 10 minutes for inspection. This doesn't include the extra time for when your inspection reveals something wrong, lol. Then hello, you get to start all over. Pay 20 cents and you can eliminate this 20 minutes AND all the time for errors, because you can actually do toner transfer without any errors. And the soak/peel takes 5 seconds.

author: sasa
author_rank: Regular Contributor
timestamp: August 15, 2017, 07:06:22 am
content: Quote from: KL27x on August 15, 2017, 06:08:03 amThe whole point is ability to make decent quality prototype PCBs almost immediately without any special tools and parts.Press&Peel foil would cost me personally 5 Euro per single A4 sheet. And only if local store have it in stock, usually does not, as no one buy it. If I would have possibility to get it for reasonable price as $1.20 I would certainly buy it, however I do not. Then use it what is the most suitable for quite decent results...Even with Press&Peel foil, garbage boards can be done as result if all other steps are not performed well. Hopefully, I have spent whole A4 copper board during initial experimentations 10 years ago, now garbage is excluded. I do not produce it much, in average once per month, at most.

author: KL27x
author_rank: Super Contributor
timestamp: August 15, 2017, 07:38:41 am
content: If you're talking abouthttp://www.techniks.com/,I agree it's not always perfect, either. It is not even close to ease of use and margin for error you get with Pulsar. iME, it takes more heat on the low end with PnP vs even regular printer/mag paper. Whereas Pulsar takes less. The PnP plastic is an insulator to the heat, and it requires a higher minimal adhesion of toner for it to be able to rip out the plastic film, rather than the other way around. On the high end of temp, the plastic will start to distort/melt; compared to Pulsar where I can shoot 1200W heat gun at full power right on the paper, an inch away, with no worry). And unless you buy 100 sheets at a time (which I have, twice, because despite its cost and drawbacks, it is still a bit better than regular paper for the lack of paper fibers and distortion and lack of soak time, when you get it right), it is more expensive than Pulsar in the US. It's not incredibly difficult to get a good transfer with PnP. But it's not incredibly difficult to get a 99% transfer with 1% problem (in a corner or edge... it's always near the damn edge) that makes it unusable.Pulsar is the good stuff. If you can't get it in Europe, that's too bad, because it really is that good. I have 50 sheets of PnP collecting dust. In the US you can buy it from Digikey and Mouser. While you're spending 7.50 on shipping for that last part you need, anyway.https://www.digikey.com/product-detail/en/pulsar/50-1101/182-1003-ND/3386They (Pulsar) also sell a foil which may help reduce porosity in ground planes. I purchased 3 packs of this film the first time I bought 3 packs of the transfer paper, and I have only opened one package just to look at it. It's a long roll of wafery thin plasticky material (not unlike dry film photoresist, I imagine), and after seeing results without it, I never even bothered to try fooling with this hassle. Results with just the paper, using my printer and process, are way better than I even hoped.Speaking of which, one of the bonus niceties which makes Pulsar >>> PnP is simply the handling. It handles like thin cardstock. It's a dream to handle, cut, apply. PnP is slippery curly/staticy plastic and more annoying and time-consuming to handle.Someone in Europe needs to start importing this stuff.

author: anishkgt
author_rank: Frequent Contributor
timestamp: August 15, 2017, 08:40:55 am
content: Out of experience i can say Toner transfer needs some experience and if the paper is not good enough like not glossy enough it would ruin during etching process (dipping in Ferric Chloride).I then moved to Photo resist which is much better and easy to do. You can use normal CFL also but i'd recommend UV or even better get a photo resist PCB which already comes with the photo resist material.

author: KL27x
author_rank: Super Contributor
timestamp: August 15, 2017, 10:59:41 am
content: QuoteI'm beyond pedantic, at this point. Probably borderline mentally ill. I can't stop myself.Unless you can achieve resolution finer than 8/8, there is nothing significantly important which is better or easier about photoresist for me, personally. At this level of resolution, it is my printer which fails, so perhaps with better printer we could even remove this limitation. I'm not sure if inkjet has better resolution, giving photoresist the edge, or if, perhaps, a better laser printer can do so. But trying to print 6 mil trace, I can see occasional break in the print, even on the paper. Perhaps with photoresist you can stack two very thin papers to get finer resolution around limitation of print, but...Personally, I don't want to make a DIY board with traces any finer than 8/8. 30 AWG wrap wire is 10 mil in diameter. If you make prototype board which you can't easily modify, you may waste a lot of time with multiple iteration. Personally, I save the really tight layout and trace for final production board, and even then only where/when absolutely necessary. Most of my production boards will be 10 mil traces for same reason I do them at home. I like a board that is moddable/repairable, not disposable. And if you order your board panelized, you will see even the manufacturer has significantly lower than 100% yield with finer pitches. (Even at 10/10).If you do not have access to the tools I use, that's a shame. But there is nothing hard or unreliable or unrepeatable about toner transfer the way I do it.I can see potential benefit in photoresist for mass production, esp for finer trace. You can make multiple attempts at making a good template. And after physically screening them under the microscope, you can use the best one and then crank out relatively high yield. Also, with transparent/tracing papers, you can potentially get good enough registration for double sided boards with less time/effort.

author: ptricks
author_rank: Frequent Contributor
timestamp: August 15, 2017, 11:37:26 am
content: Toner transfer method:If you go with this method look for an older printer, something like the hp laser jet 4. Old but prints very dark on the paper.Iron or laminator , buy a laminator for about $20 , the iron can work but it really isn't ideal .Paper, magazine paper worked best for me , but it had to be attached to another regular paper sheet , feeding it through the printer wrinkled magazine paper, but taping another sheet to it worked.Photoresist:I now use the photo method because it is really easy and low cost. I put the film on the board, run it through laminator twice and done, board is ready to expose.I print the image onto transparency sheets using a laser printer. inkjet printers use dye based inks and can allow the uv light to pass through.Developer can be purchased on ebay usually from the same people selling the film.If you want to save cost you can buy from a chinese vendor, it is usually the same stuff manufacturers use and cheap because it came off the unused rolls from production runs.Exposure lamp I use is a regular fluorescent lamp , takes about 15 minutes.Etchant - I use the peroxide method, but try to find somewhere that sells hair and beauty products, they have the stronger solutions that contain less water.If you want to save time you can laminate a bunch of boards with the film and store them in a dark place until needed, the film will last months when applied, then when needed you just print your design, expose , develop , and etch. You can do a board in 30 minutes , and most of that is just waiting for the exposure time and etching.You may read about needing a dark room with yellow light bulbs or some such thing, but I have learned that the resist film isn't that sensitive to light and I now just do it in a room with low light but not anything dark like you would need for camera type setups.If you use the positive photo resist you get an added benefit in that after etching the resist can be left on the board and acts as a mask for the traces that protects them from oxidation .

author: KL27x
author_rank: Super Contributor
timestamp: August 15, 2017, 07:38:36 pm
content: If you have Mouser service in EU, it's essentially same price as here.http://eu.mouser.com/ProductDetail/Pulsar/TONER-TRANFER-PAPER-50-1102/?qs=%2fha2pyFadujK5gk6R5%252bg4RvuMs6ieUwGkHlMXYmNwftaMGnYTnrRwA%3d%3dIf you don't live in EU, don't clink on that link. If you're curious of other locations you can "change location" to the right of the cart icon on the Mouser webpage.So if this is correct, 10 pack of Pulsar is 12.74 Euros anywhere in the EU. 17.37 funny dollars in Australia. 58,11 lei in Romania. But Mouser's shipping charge is much higher in EU, unless you meet minimum order of 50 euros (then it's free), which I think many people could manage a few times a year.A pretty hefty markup if you had to buy it from Amazon:https://www.amazon.co.uk/TONER-TRANFER-PAPER-50-1102-Pulsar/dp/B017V3SSDO/ref=sr_1_2?ie=UTF8&qid=1502825771&sr=8-2&keywords=pulsar+paperIn US, Digikey even sells in 3500 sheet discount, lol.https://www.digikey.com/products/en?keywords=pulsar+paper&pkeyword=pulsar+paper&v=On the website, Pulsar claims 5 mil minimum trace width. I would not be surprised if this is technically possible, but I suspect very few people own a laser printer capable of achieving this. At this point, you may also need to customize the driver and/or do some intermediate processing tricks. And even then, you would probably need a relatively new drum and quickly lose this resolution if you used the printer for much of anything else. Practically, 8 mil is what I call it, with any common equipment and low maintenance cost.IMO, UV method will be relegated to specialized users - the kind who do thru hole plating and diy soldermask and who modify laser printers to try to get finer traces. It may take time, but one day the bulk of hobbyists will look back at photoresist with nostalgia.

author: tooki
author_rank: Super Contributor
timestamp: August 17, 2017, 11:06:53 pm
content: Quote from: ptricks on August 15, 2017, 11:37:26 amThough I still agree that a laser is usually better, just FYI, most inkjets now use pigment black ink, even if the other colors are dye. My inkjet, for example, actually has pigment black for plain paperanddye black for photo paper, since pigment black causes metallic sheen on glossy paper. (Color pigment inkjets also exist, since the pigment inks are far more lightfast, but at the expense of somewhat reduced color accuracy.) It's eminently possible to use a pigment black inkjet for photoresist exposure.

author: janoc
author_rank: Super Contributor
timestamp: August 18, 2017, 11:34:27 am
content: Quote from: Beamin on August 14, 2017, 09:29:27 pmUmm, what do you mean by "no toxic waste"? Aka copper compounds, very acidic and corrosive etchant, bad corrosive (and very nasty, possibly lethal if inhaled!) fumes are not toxic enough for you? Compare that with the other etchants - actually out of the common stuff the acid+peroxide combo comes out as the worst one, mainly because of the high acidity necessitating neutralization before disposal and the fumes (the copper compounds are about the same with all the etchants). I would say you should do your research on this first before you make such claim.The disadvantages of using HCl as etchant are well documented, even on this forum. I am not going to rehash them. Do a research on trace undercutting and you will see right away. It is a very poor quality etchant for a reason.

author: Zero999
author_rank: Super Contributor
timestamp: August 18, 2017, 02:19:37 pm
content: Quote from: KL27x on August 15, 2017, 07:38:36 pmI doubt that. What's more likely to happen is the bulk of hobbyists will stop making their own PCBs altogether.As far as I'm aware, there's only one maker of the proprietary paper you like. What happens if they go out of business? The photographic process is actually used by professionals and there are plenty of suppliers of the materials required to do it.

author: tooki
author_rank: Super Contributor
timestamp: August 18, 2017, 03:08:58 pm
content: Quote from: Hero999 on August 18, 2017, 02:19:37 pmDid I miss something? All I've seen mentioned here is toner transfer paper, which is in no way proprietary; many brands exist, including no-name stuff on eBay.

author: Zero999
author_rank: Super Contributor
timestamp: August 18, 2017, 04:22:19 pm
content: Quote from: tooki on August 18, 2017, 03:08:58 pmThe type mentioned by KL27x is Pulsar. I'm not surprised there are alternatives available (I haven't done any research because it doesn't interest me) but are they exactly the same as the branded product? I doubt it. The toner transfer process is dependant on many factors. Change one of them and you have to experiment a bit to get it working again.

author: janoc
author_rank: Super Contributor
timestamp: August 19, 2017, 09:16:57 am
content: Quote from: Hero999 on August 18, 2017, 04:22:19 pmActually most people don't use the Pulsar paper (or any special paper) at all - it is expensive and may not be easy to get, depending on locale. Normal printer or magazine paper works fine for most. Yes, you have to experiment, the results may not be as good but that has hardly ever stopped anyone.

author: KL27x
author_rank: Super Contributor
timestamp: August 19, 2017, 10:12:01 am
content: The founder of Pulsar got the idea in 1992, after watching silkscreen graphics product which used similar paper, which was shortly after Press N Peel came onto the scene.I don't know how I first heard about it, but I'm pretty sure it was through DIY community/maker websites, sometime around 2011ish, when I first learned about dextrin coated paper. And shortly after that, about Pulsar. If you care to search, you can find instructions for making your own dextrin-coated paper, even.There are some "toner transfer" papers sold on eBay, which are very cheap. I bought 100 sheet pack to see what it was. They were nothing more than printer label backings, and TBH, I'm ashamed to say I threw them away without even giving them a shot.. Maybe they are great?

author: sasa
author_rank: Regular Contributor
timestamp: August 19, 2017, 10:26:18 am
content: Quote from: janoc on August 18, 2017, 11:34:27 amI have quoted this as well, but missed to comment...Nothing much to add to janoc comment, except that you may use 1L of Ferric Chloride almost forever, if only add small quantity domestic use HCl when bath start to weakening. It is not the same, but "the green bath" (Cupric Chloride + HCl) is corrosive almost as fresh Ferric Chloride. I have used that when it was not easy to find fresh Ferric Chloride.As well be double careful when etch at winter, when bath must be warm up. Ferric Chloride will work best between 25 and 40C, but never exceed that or boil it! That is the reason I put on hold all etching when outside temp is under 25 - always etch outside.This may sound a bit overwhelmed, but with acid there is no game, especially if there is no specially quite well ventilated room for that. As I produce less then one prototype per month in average, nothing special I really need.

author: Zero999
author_rank: Super Contributor
timestamp: August 19, 2017, 01:36:19 pm
content: Quote from: janoc on August 19, 2017, 09:16:57 amYes, I've done that myself before. My favourite is magazine paper. I've found that the more ink on the page the better.QuoteHence why I prefer the photographic process. No doubt I could get better results with toner transfer if I purchased a laminator and used special paper, but I already have a UV exposure box and some pre-sensitised copper clad board and I'm more comfortable with it because it seems more professional.Sadly I don't do much hobby electronics or making my own PCBs nowadays.

author: M4trix
author_rank: Frequent Contributor
timestamp: August 19, 2017, 01:57:42 pm
content: Why are you guys so afraid of HCl and peroxide ? I have been using this etchant almost 30 years and I'm still alive and kicking !My lab ( bathroom) is clean, no stains, nothing has corroded. Well, recently I switched to sodium persulfate. The main reason was, it isodorless. The only downside is its short shelf life.

author: tautech
author_rank: Super Contributor
timestamp: August 19, 2017, 07:49:39 pm
content: Quote from: KL27x on August 19, 2017, 10:12:01 amWaxy label backing paper works great.The toner releases easily so the transfer needs to bond it well to the PCB so it stays put.These papers work very well in my HP 6MP at 600dpi but not so well in my 1200dpi Oki.I use ordinary printer paper as a backing with a piece of waxy paper stuck to it that's a bit larger than the PCB.

author: KL27x
author_rank: Super Contributor
timestamp: August 19, 2017, 08:28:50 pm
content: QuoteI wonder if you just peel the paper off? Or do you still soak it in water? Also, I'm curious what happens in the Oki which makes it not so good? Does it looks fine when it comes out of the printer, but the toner falls off/smudges before you can get it on the board? Or does it print fuzzy out of the gate? Perhaps certain kind of toners/printers don't stick well enough to this kind of paper.It was very unlike me to not try it. I love it when I find cheap tools that work. When I bought it, I was kinda hoping it was going to be dextrin coated paper from china, or that maybe it was some kind of improved PnP, or that maybe it was some different technology altogether. I had a nagging fear that the waxy surface might degrade the accuracy of my printer. And I balked. I have broken 3 laser printers in the last decade trying things which seemed innocent enough at the time.*The dumbest thing I did was try to print directly to a plastic mailer. The most recent thing was realizing I made an error about 3 seconds after hitting "print" on a 400 page document, and turning off the printer with the power switch to prevent it from printing. Yeah, that completely broke the printer. Next time I'll remove the paper.

author: tautech
author_rank: Super Contributor
timestamp: August 19, 2017, 10:47:24 pm
content: Quote from: KL27x on August 19, 2017, 08:28:50 pmIt's either too much toner or the wrong brew to get sharp traces with the Oki and TBH I haven't tried to sort it for waxy backing paper. I've used a few types all saved from the bin and tucked away until I needed it. Some was from rolls of vinyl contact sheet, rolls of labels and others A4 sheet of labels.I only changed to my Oki to reduce porosity for the ground pours and used highest density prints when maybe the Oki would give the result needed at 600dpi where the HP wouldn't. Need to try some more settings......Any of these waxy backing papers provide a good medium for toner transfer if you can get the recipe right.

author: Zero999
author_rank: Super Contributor
timestamp: August 20, 2017, 08:35:48 am
content: Quote from: KL27x on August 19, 2017, 08:28:50 pmSo you think the printer broke because it was turned of when it was just about to print? If that's really the case, then it's dumb design. I could understand it causing a paper jam or having to do some kind of reset process, then next it it was powered up but a power cut shouldn't break the printer.

author: janoc
author_rank: Super Contributor
timestamp: August 20, 2017, 01:43:58 pm
content: Quote from: M4trix on August 19, 2017, 01:57:42 pmNobody is "afraid". However, there are much better etchants out there and, especially for a beginner with little understanding/experience in chemistry, it is difficult, even irresponsible, to recommend acid+peroxide as a good option. Out of the commonly available options it is the one with the largest potential for problems.That nothing has corroded for you and you didn't make a big mess doesn't mean someone else won't.

author: sasa
author_rank: Regular Contributor
timestamp: August 21, 2017, 05:21:31 am
content: Quote from: M4trix on August 19, 2017, 01:57:42 pmPerhaps it better to clear up a bit why that is not at all good combination for beginners...Highest precaution measures when use one of the strongest known non-organic acid is mandatory. No mistake is allowed.Who do not know that HCl's aggregate state is gas, plays with death. And that does not know many beginners. HCl (gas) is easily dissolved in water, when we know it as HCl acid, i.e. muriatic acid. Dissolved in water, we have extremely reactive Cl+ ions which will react with almost anything. If water is gone, it will returns to original aggregate state - gas. And that makes it extremely unstable and hazardous. Inhale gas and you will have one of the strongest known acid in your respiratory paths and lungs, serious tissue damage and death, depending on quantity of inhaled gas...In short, the main problem with HCl acid and peroxide is that is extremely unstable. Finding clean 10% peroxide as well is quite a problem (otherwise can end up with mud and/or PCB garbage) and use with exact proportion. On the contrary, Ferric Chloride is stable, can be stored indefinitely when produced and easy to use, without any additional chemicals.Regarding toxic waste. HCl acid and peroxide form Cupric (II) Chloride, while Ferric (III) Chloride produce Ferric (II) Chloride and Cupric (II) Chloride. These are extreme toxic and still highly corrosive. If not used further, must be neutralized by a base first, which again is extreme exothermic reaction and must be done with extreme caution. Only then dispose it by strict regulative most countries have...Doing etching outside or in well ventilated room specifically made/adapted for that, alway wearing plastic gaggles, plastic gloves and have container with dissolved baking soda with immediate access to tap water, is a minimum of precaution measures.Being well informed about exact process and all risks is mandatory.

author: tggzzz
author_rank: Super Contributor
timestamp: August 21, 2017, 10:45:43 am
content: Quote from: sasa on August 21, 2017, 05:21:31 amLet's keep things in perspective...Your stomach is full of hydrochloric acid pH 1.5 to 3.5; that's what produces the burning sensation when you vomit.https://en.wikipedia.org/wiki/Gastric_acidI've inhaled the fumes from concentrated HCl in a flask. Unpleasant, so I didn't take a second breath (and almost dropped the flask!). But no other ill effects.

author: janoc
author_rank: Super Contributor
timestamp: August 21, 2017, 11:06:27 am
content: Quote from: tggzzz on August 21, 2017, 10:45:43 amLet's keep things in perspective - try to drink some 30% hydrochloric acid, as commonly sold and used, and you will see what happens to you. Hopefully you will survive it to tell the tale.Concentration matters - the acid in your stomach is much less concentrated than the 30-36% one that is commonly sold - by about an order or even two of magnitude. pHis nota measure of how dangerous the acid is - e.g. lemon juice has pH of about 2 as well.Moreover pH is a logarithmic scale, so there is a huge difference between something having a pH 1 and something with pH 2.And re inhaling the fumes and having no ill effects - hum, you may have had chemical burns in your lungs/trachea without even realizing it (HCl gas + water in the mucus -> liquid concentrated acid on your tissues). If one doesn't inhale a lot of it the body usually recovers over time.However, inhale a bit more (not even directly from the bottle - it is enough to have the fumes around in sufficient concentration) and you have an edema which could be a life threatening situation because the burned tissues swell up and you will suffocate. Breathing this stuff is an incredibly stupid idea.

author: tggzzz
author_rank: Super Contributor
timestamp: August 21, 2017, 01:49:23 pm
content: Quote from: janoc on August 21, 2017, 11:06:27 amThat's a mixture of useful facts and strawman arguments. Yes I do appreciate your safety notes, but they aren't a reason to betoofrightened of hydrochloric acid.My father was content to bring the conc HCl home from the lab on public transport in a plastic container in his overcoat pocket, and give it to a 12yo to play around with. Now my fatherdidknow what he was doing; the acid that really frightened him was hydrofluoric acid. ISTR one of my uses for HCl was to make hydrogen sulphide; I stank the kitchen out several times.Then at school when we were 14/15yo, we were given small pieces of metallic Na or K, I forget which, and told to describe what happens when we put it in water. Conc H2SO4was readily available on every bench, and it is really entertaining to watch its reaction with granulated sugar. Our first A-level (16-18yo) chemistry lesson consisted of getting every (>50) chemical out of the cupboard, and every student describing its smell; I never could distinguish between rats' piss and mice' pissWe were warned, however, to be careful when cleaning the potassium cyanide out of our equipment, to make sure there was no acid in the sink.Yes, we did slosh liquid mercury around trays. Yes, one of my friends' watches was noticeably more powerful that the schools' most powerful radioactive source - and was sent away to be destroyed at Harwell. Yes, when someone in front of me set the contents of his flask on fire, and calmly extinguished it using an asbestos tile, the teacher's only reaction was "well done".Yes, we all survived.No, we didn't have the apparatus described in some of my 1930s "Boy Electrician" book: fun things to do with your x-ray machine (but if your skin turns red you are probably using it too much).

author: janoc
author_rank: Super Contributor
timestamp: August 21, 2017, 05:57:06 pm
content: Quote from: tggzzz on August 21, 2017, 01:49:23 pmCare to point out the strawman? Because I somehow don't see it. However, you are providing plenty of anecdotal evidence about doing stupid stuff where you didn't get hurt mostly by blind luck. And yes, I have actually a lab training (not just the normal school stuff).I am not saying one should be frightened of hydrochloric acid - there are many way worse chemicals. However recommending it to a newbie that has possibly seen chemistry last time when in school (and even that was just watching the teacher blow some shit up) is irresponsible when there are safer means available.

author: KL27x
author_rank: Super Contributor
timestamp: August 22, 2017, 04:02:48 am
content: @hero999 yeah, right. The printer was spooling i think. It hadnt even started printing yet.. i flipped off the power switch on the printer. But otoh, it was 2 years old......I am 99% sure this kind of thing will absolutely not break a printer that is still under warranty. There is an internal calendar which flips the kill switch at the right moment. Now, everything out of the ordinary can break the printer.The funny thing is all the LEDs turn on when u flip it on for a split second. And then they all go dark. The manual lists several eror codes by led, and this is of course not one. It is my assumption this is the "play dead" function put in by Brother programmers.It doesn't even bother me, anymore. It's expected. I just wish they'd hurry up and put a credit card swiper into the device. So instead of buying a new printer, I have the option to just buy this one back for another 2 years and get on with it.

author: tggzzz
author_rank: Super Contributor
timestamp: August 22, 2017, 10:12:48 am
content: Quote from: sasa on August 22, 2017, 09:16:18 amNot unreasonable, but that reference was merely the first I googled. Here are some others, and you canveryeasily find this information (even in basic school biology textbooks!):http://www.bbc.co.uk/schools/gcsebitesize/science/add_aqa/proteins/proteinsrev5.shtmlhttp://www.med-health.net/function-of-hydrochloric-acid-in-stomach.htmlhttps://www.scientificamerican.com/article/why-dont-our-digestive-ac/QuoteYes, it is full of HCl - as well as enzymes; see references above or spend 30s googling for yourself.QuoteThat's more difficult. Firstly I agree that you must be very careful w.r.t. risks to anybody that just happens to be in the vicinity.However, youcannotremove all risk, and to attempt to protect kidstoomuch is counterproductive. It is best if you teach kids to recognise risk, assess risk, work out how to reduce risks to an acceptable extent.That's what I did with my daughter, and although at the time she thought I was "wrapping her in cotton wool", she has later come to realise that isn't the case. Examples: I started sending her up trees at 10yo, then moved on to aerobatics at 15 and solo pilot at 16, backpacking around India at 12, a 2m deep hole in in the kitchen floor throughout childhood, broken knee skiing, etc. Consequently I wasn't worried when she bought a ticket to travel around Australia on her own at 18 (although I was glad she hadn't chosen Laos and Cambodia!)/QuoteIndeed, but there is a need to keep a perspective of which risks are most likely to hurt you badly. It is human nature to downplay the importance of everyday risks, and to concentrate on rare risks.Hence at my age merely living exposes me to 75-200 micromorts per day. (https://plus.maths.org/content/os/issue55/features/risk/indexhttps://en.wikipedia.org/wiki/Micromort) That means it is rational for me to takemorerisks than I was younger.QuoteThey weren't "pranks". The risks and consequences were assessed beforehand by knowledgeable people. With, as I noted, the notable exception of my taking one breath of the HCl fumes!QuoteUnderstanding is of key importance to risk assessment.Consider that I have had mercury in my mouth for 50 years. Medical opinion is that it should be left there unless the amalgam filling becomes loose.QuoteShrug. They aren't the only incompetents!Assess risk. Assess how to reduce risk. Keep risks in proportion.

author: sleemanj
author_rank: Super Contributor
timestamp: August 22, 2017, 10:20:48 am
content: One day I'm going to open a cotton wool factory, not cotton buds and swabs, I mean huge human sized cotton wool bales. Then everybody can wrap themselves up and be nice and safe from the world.

author: KL27x
author_rank: Super Contributor
timestamp: August 22, 2017, 10:24:30 am
content: Practical safety tips:30% fumes are potent. Mix it outdoors.Acid into watta.Safety glasses.Bucket of water for emergencies. Gloves maybe. But bucket of water > gloves, imo. Dilution is the solution.If u have the big gallon jug, it is often easier to use a turkey baster or large pippet to take some acid out of the bottle without pouring.Eye protection is the main concern. Dont spill it all over ur crotch is probably a good idea. Dont transfer it into any other container. Dont mix it with bleach unless u want to poison yourself.Oh, probably a bad idea to try to handle it on the ground. U dont want your face over an open bottle. If it sloshes, u can splash a droplet into an eye. And fumes. And if ur sitting, u got the whole spilling it all over ur croth, thing. U want a sturdy table/bench of some kind u can stand upright to keep the stuff at arms reach.

author: sasa
author_rank: Regular Contributor
timestamp: August 22, 2017, 11:42:34 am
content: Quote from: tggzzz on August 22, 2017, 10:12:48 amSure, but still (back to the issue), that is not explanation why is better to force pure beginner (with no experience at all in etching techniques) right to the HCl acid + peroxide. That is not answered precisely and unequivocally.Ferric Chloride (also cheap) is stable, safer, easy to work with... all already pointed. While HCl acid + peroxide is quite opposite.Answer is more than obvious to me.

author: tggzzz
author_rank: Super Contributor
timestamp: August 22, 2017, 02:23:06 pm
content: Quote from: sasa on August 22, 2017, 11:42:34 amI don't disagree with that - and nothing I have written implies otherwise.

author: Alex Eisenhut
author_rank: Super Contributor
timestamp: August 22, 2017, 02:40:48 pm
content: And in any case, make sure your laser printer is actually able to print correctly. Apparently HP are still working on this.

author: sasa
author_rank: Regular Contributor
timestamp: August 22, 2017, 04:00:43 pm
content: Quote from: tggzzz on August 22, 2017, 02:23:06 pmSorry then for misunderstanding. Your every post implies to me that you have quite relativistic approach regarding HCl and recommends it to beginners. This is quite important healthy issue and may be quite confusing to beginners what to choose with different suggestions.I have also deleted recent message have nothing much regarding the issue, in order to clean up a bit this quite long thread as well.Sorry again.

author: tggzzz
author_rank: Super Contributor
timestamp: August 22, 2017, 04:35:56 pm
content: Quote from: sasa on August 22, 2017, 04:00:43 pmNo problem.I've never used HCl for etching PCBs; ferric chloride has been sufficient for me. Idothink caution is required and that beginners should be made aware of the possible dangers.OTOH, HCl is readily detectable(!), the natural instinct will be to rapidly move away it, and unless you are careless enough to spilland leavesome in contact with your skin, it is unlikely to do you too much harm. Hence I don'tfearHCl - but do treat it with respect.What do I fear? Botulism in pre-packaged foods. HF (surprisingly nasty stuff). 400mW BluRay lasers used for etching on reflective surfaces without being completely enclosed. Death cap and destroying angel. Why? Because they are undetectable untilafterthe damage is done, and they can damage other people.QuoteI don't see any need for you to apologise.As far as I can see, all your posts were written with the best intentions - all that has happened is that we have placed differing emphasis on certain aspects of the subject being discussed. It isnota case that I/you are right and you/I are wrong. Hopefully the OP will learn from our discussion and be in a better position to make their own informed choice; goodPersonally I must admit to disliking deleting messages unless they are actively dangerous or actively offensive. I don't think yours fall into either category

author: M4trix
author_rank: Frequent Contributor
timestamp: August 22, 2017, 05:08:16 pm
content: OK, but what about OP ( Beamin ) ? He's not responding. Probably you scared him with this acid debate.

author: KL27x
author_rank: Super Contributor
timestamp: August 22, 2017, 10:34:07 pm
content: Nah. He's probably building a super computer, already. While we sit around in forum circle jerk.QuoteI think it's important to concentrate on irreversibly damaging risks. Concentrated HCl can scar your cornea pretty quick. If a large spill happens, (and who has never spilled anything?), it could cause some bad burns, if you don't have a large quantity of water immediately available.OTOH, for those of us who handle HCl, frequently, it is now an everyday risk. We might forget there are certain things we automatically do which make it relatively safe for us to handle.I remember having quite a hard time managing it the first few times I used it. And it's because I did it completely wrong. No bench. No pipette. Managing a full-to-brim gallon jug with no bench and trying to get it into shallow glass tray without splashing, and all while holding my breath b/c I'm doing it hunched over the ground, putting me in the fume-zone. It was wake-you-up dangerous. With the right tools, it's not even a thang. If I managed to burn my eye because I was too excited to make a board to wait for the right equipment, it would have been a shame. It's easy to take it for granted, in hindsight.

author: tggzzz
author_rank: Super Contributor
timestamp: August 22, 2017, 11:10:51 pm
content: Quote from: KL27x on August 22, 2017, 10:34:07 pmAgreed, particularly if there are no early-warnings that "here there be danger". In my experience, HCl fumes were a sudden early-warning jolt of reality!QuoteAgreed. Assessing, understanding and containing risk is very important. But I try to minimise the number of times I "just say no" by restricting them to the occasions when the benefits are insufficient.An example of this... When my daughter was learning to fly gliders, one old instructor that had started out in pointy-jets 50 years ago, said "you have to expect to lose a few ". Some people would have been horrified, but I merely grinned. I knew he was extremely safety conscious and extremely competent, and that I could entrust my daughter to him. e.g. on "low energy" approaches where you have to fly accurately or you will "spin in". Or when deliberately entering spins at ~1000ft so the aircraft has "departed from controlled flight" and is descending at ~100ft/s and to recover you have to dive harder at the ground.QuoteI was woken up fast by breathing in the fumes.I've also pippetted a small amount of acetone into my mouth because I didn't notice I was also entraining air. I spat the acetone out fast, with no known ill effects.

author: janoc
author_rank: Super Contributor
timestamp: August 22, 2017, 11:41:48 pm
content: Quote from: tggzzz on August 22, 2017, 11:10:51 pmAcetone is fairly tame if you don't swallow it or keep it in your mouth for too long. Not that I recommend such technique.However, if you tried to do that with an acid, your experience would have been rather different. It may sound like a very stupid thing to do (and it is!) but I have seen a lot of evenhighly trainedpeople suck acids and such into a glass pipette using their mouths instead of getting one with the balloon at the end

author: tggzzz
author_rank: Super Contributor
timestamp: August 23, 2017, 06:43:27 am
content: Quote from: janoc on August 22, 2017, 11:41:48 pmIndeed. Doing that with acetone was stupid/dangerous enough!And your point about highly trained people is valid in many contexts. My favourite example is that, although gliding is pretty safe, about 10% of top competitive pilots have killed themselves by pushing the envelope too far.

author: Beamin
author_rank: Super Contributor
timestamp: August 23, 2017, 10:56:09 pm
content: Quote from: janoc on August 18, 2017, 11:34:27 amI'm currently working on a BS in organic chem so when I do my actual home work does that count as "doing my home work"?When I say less toxic it means I can safely convert or dispose of the waste at home. HCl when poured down the drain gets diluted. HCl can be used to unclog drains. 92% sulfuric acid is often sold as drain opener.What you don't want is heavy metals dissolved in solution then pour them down the drain. I can recover the copper from used HCl in some fun experiments or make other compounds out of it. HCl is a fuming acid but if you have been around it you will see why you wouldn't breathe in the fumes: getting just a little bit of the fumes in your nose is quite unpleasant and your body will just stop breathing it in. Plus I just like dissolving things with acid. I put a circuit board in HCl for a week and it made several color changes before leaving just the board and turning the components into "sand" at the bottom of the container. Not much was left except the wrapping of the caps and some plastic.

author: M4trix
author_rank: Frequent Contributor
timestamp: August 24, 2017, 01:05:25 am
content: Looks like @Beamin isn't afraid of HCl after all. Actually, he's doing weird things with it.Well, the conclusion is: ferric chloride lobbyists has lost the debate !

author: sasa
author_rank: Regular Contributor
timestamp: August 24, 2017, 04:54:00 am
content: Quote from: M4trix on August 24, 2017, 01:05:25 amThis is not about winning or losing, but about maximum safety - not only Beamin (who did not mentioned the "minority fact" that he studding chemistry) reads this thread. I do not regret a bit spent some time in this thread writing some words of extreme caution.It was actually not rare accidents when trucks with tanks of HCl are turned over on highways or leaks from industrial plants. The whole wide area is alarmed and brief actions are performed for recovery. Sadly, that is not the case with other types of pollution, which kills quite slowly.

author: tggzzz
author_rank: Super Contributor
timestamp: August 24, 2017, 07:13:01 am
content: Quote from: sasa on August 24, 2017, 04:54:00 amYes indeed.(But I would replace "maximum" with "appropriate proportionate")

author: Zero999
author_rank: Super Contributor
timestamp: August 24, 2017, 02:30:33 pm
content: Quote from: tggzzz on August 22, 2017, 10:12:48 amThat site ignores the benefits of taking extra risks, for example a car may safer, in terms of the chance of dying per mile, than walking and cycling, but those who are more active, have a lower risk of life threatening health problems, such as heart disease and diabetes.A similar thing could probably be said about young people, who do risky experiments: they have higher chance of being killed, as a result of said experiments, but also a greater chance of getting a good job, which leads to better health and a longer life expectancy.

author: tggzzz
author_rank: Super Contributor
timestamp: August 24, 2017, 03:11:48 pm
content: Quote from: Hero999 on August 24, 2017, 02:30:33 pmThe reason for posting the URL was so that people could understand what a micromort is. The site does not attempt to quantify all risks (let alone suggest courses of action!), and hence doesn't "ignore" them.There are far better and more direct reasons for getting young people to do "risky things" than merely possibly getting a better job:when, not if, they make mistakes, the mistakes will be in somewhat controlled circumstances and will probably have less serious consequencesthey learn to assess risks, balance risks/rewards, and to think about how to ameliorate risksthey will be less inclined to see any attraction in "standard teenager risks", e.g. riding a motorcycle too fastIt is possible that those qualities will enable them to get a job they enjoy more - partly because they know what they enjoy, partly because they can demonstrate (cf merely claim) mature responsible behaviour.

author: sasa
author_rank: Regular Contributor
timestamp: August 24, 2017, 05:11:58 pm
content: Quote from: tggzzz on August 24, 2017, 03:11:48 pmThere is one big problem with that - it will learn not to appreciate not only their own life, but no body else. And then it is open path to walk over dead bodies and use any means to achieve any goal they imagine... The history is full of such people.Etc, etc...Perhaps it is better to open new topic in "General chat", as difference between controlled environment experimentation and life dangerous experimentation is indeed diametrically opposite and deserve it's own discussion.

author: tggzzz
author_rank: Super Contributor
timestamp: August 24, 2017, 05:28:50 pm
content: Quote from: sasa on August 24, 2017, 05:11:58 pmThose two behaviours are orthogonal.QuoteArguably that ismorelikely with those people thathaven'tbeen exposed to risk, and therefore haven't learned how to assess and deal with risk.

author: Zero999
author_rank: Super Contributor
timestamp: August 24, 2017, 08:08:14 pm
content: Quote from: tggzzz on August 24, 2017, 03:11:48 pmIn theory yes, but I think you've overlooked psychology. People often don't think rationally in the heat of the moment, when adrenaline is involved. I'm quite sure if you showed a group of teenagers, a video of someone driving dangerously and killing others as a result, they'd all condom the driver, but in reality, some of them will go on to drive dangerously, regardless of what they've said in the past. Once a testosterone pumped teenager sits behind the wheel and experiences adrenaline when driving fast, they get rewarded for their risky behaviour and do it again, until something happens, usually a near miss, then they calm down for awhile.This flies in the face of what you said earlier, about being older, means it makes more sense for you to take risks, than a younger person, when in reality the young are more prone to risky behaviour. Perhaps younger people have more to gain from taking risks?

author: tggzzz
author_rank: Super Contributor
timestamp: August 24, 2017, 08:31:15 pm
content: Quote from: Hero999 on August 24, 2017, 08:08:14 pmSigh. The training and controlled exposure to risks is the best way I know to ensure that people aren't attracted to chasing adrenaline dangerously, and in the heat of the moment people aren't overwhelmed and do act rationally. If you know of any better way,dotell us all.I know that worked extremely well with my daughter (including when her life was in imminent peril), and with her friends that had similar training and exposure. OTOH, those that didn't...QuoteSigh. Younger people being more prone to taking risks and it not being silly for older people to take risks are two completely orthogonal issues; they cannot be compared.

author: Zero999
author_rank: Super Contributor
timestamp: August 24, 2017, 08:51:20 pm
content: Quote from: tggzzz on August 24, 2017, 08:31:15 pmIt looks like we agree.Do you have any sons?

author: Beamin
author_rank: Super Contributor
timestamp: August 24, 2017, 11:38:19 pm
content: Few things:HCl(aq)-> H+ and Cl(-) chlorine is an oxidizer with a charge of -1 because it has 7 valance electrons and things become "balanced" at 8.Most people on the internet that post about things being so dangerous have never worked with them; only reading a Wikipedia article or maybe an MSDS. The HCl fumes is a good example. Your body doesn't let you breathe in the HCl gas. Its like trying to stick your hand in fire as soon as it gets close you jerk back involuntarily. Yes you can breathe in HCl but even in a room full of it you would probably hold your breath until you passed out. Anyone who has spent 5 minutes with the stuff would know that. I tend to ignore the "its so dangerous you should NEVER do that" people because they fear what they don't understand. That's how you get hurt.People also have to realize that no matter what you say they are going to do it anyways. So instead of trying to talk them out of it provide useful info on the subject so they can make educated risks. Its like telling your kid to wait until marriage for sex to prevent them from getting STD's. Instead of telling them what STDs are you just tell them no sleep overs and go to church. Since you wasted your time preaching abstinence your kid could get aids unknowingly then spread it around because you assumed that its a perfect world where abstinence only is realistic.Maximum safety is a fallacy. If you are going for maximum safety you are not going to make your own circuit boards. You aren't even going to make your own circuits as you could get shocked, burnt, or start a fire. You won't get anywhere in life if you don't take some risks.As mike rowe from dirty jobs says "safety second" because if safety was first you wouldn't be out catching crabs or changing light bulbs on bridges or antennas. Nothing risked is nothing lost, but more importantly nothing gained.I got to where I was in life by taking risks. Sure they were calculated and looking back I wouldn't take them again but I'm really glad I did.As an aside I have got the HCl and 3% peroxide on my skin many times I just washed it off. If you have ever worked with it you would know that. If I was using H2SO4 and peroxide that would be a very different story but you need to let people know that. If you just say ALL acid is super dangerous to get on your skin without providing all the facts that becomes dangerous. Think if someone told you ALL acids are dangerous; then they spill HCl on their skin and not much happens. Then they think "OK they were just over reacting about safety". So they make some piranha solution and get that on their skin and have to go to the ER. By not letting them take the risk with HCl you just created a bad culture of safety.There are youtube videos out where this stupid kid puts iPhones into things like lava and other destructive things. He melts crayons on his stove and it catches on fire. He freaks out and starts asking the camera saying "guys what do I do?". HES ASKING THE CAMERA OUT OF DESPERATION!!!! He doesn't think to put the lid on or put it in the stove so he nearly burns his house down trying to put it in the sink. Then he makes piranha solution with NO GLOVES. Thats just plain STUPID. No doubt others will try the experiment like he did and wont be so lucky. The it will be that much harder for me to order chemicals because a stupid news reporter says how "kids can order this off the internet then die!!!"

author: M4trix
author_rank: Frequent Contributor
timestamp: August 24, 2017, 11:51:01 pm
content: @Beamin,is that you or someone hacked your account ?

author: Beamin
author_rank: Super Contributor
timestamp: August 24, 2017, 11:58:53 pm
content: Quote from: M4trix on August 24, 2017, 11:51:01 pmWhat do you mean?

author: M4trix
author_rank: Frequent Contributor
timestamp: August 25, 2017, 12:11:56 am
content: Just a joke mate !

author: Beamin
author_rank: Super Contributor
timestamp: August 25, 2017, 12:30:59 am
content: Quote from: M4trix on August 25, 2017, 12:11:56 amYes I tend to surprise people by figuring out things that they think I'm clueless about. I often fain ignorance to get out of doing monkey work. Never tell someone you can fix computers. They will be lined up for repairs for you to get the Babylon tool bar off their 10yo laptop.

author: tggzzz
author_rank: Super Contributor
timestamp: August 25, 2017, 07:36:07 am
content: Quote from: Beamin on August 24, 2017, 11:38:19 pmYes.I haven't spilled HCl/3% peroxide etching solution on my hand, but your statement feels right, as do the sulphuric acid statements.Recognition, understanding, avoidance and amelioration of risks is a key life lesson - and that's true of electronics, chemical, driving, flying, exercise, financial, relationship, etc etc risks!

author: sasa
author_rank: Regular Contributor
timestamp: August 25, 2017, 08:39:44 am
content: Quote from: Beamin on August 24, 2017, 11:38:19 pmThat is actually quite good example. And because many people (especially kids) do extremely stupid things knowing nothing about risk and protection they jump into something carelessly (copying older as monkeys) and rely on some troll's "infos" on internet ("articles", forum, wikipedia etc), instead to get information from right sources.Go to the restaurant, for instance, and order something to drink. For 1 Euro and 5 minute break you may get Hepatitis C and STD some other as well. On opposite example, go to the dentist to get rid of caries and you may easily get similar. Buy food at some place you always visit and you may get food poisoning and die as well. Go to hospital to make simple operation and you can be dead from hospital-acquired infections. Etc... These are not examples, but real events and real people.Piloting, gliding, driving, riding motor/bike, cross the road etc... All the same, the risk is always present.The main point is, that there is many things that is not under your control and instead, must to trust some idiot on word that he done his job correctly, trust always by default and hope to the best, or learn their job as well to recognize symptoms can affect on your life as well. What you can control yourself, you doing it the best you can (learning in well controlled environment ) or not doing it at all. If want something to learn, learn it from right sources - do not rely on "infos" from internet made by unknown credibility person(s).In short, you can risk by many ways jumping into uncontrolled and controlled situations - you, your son/daughter, ... can get hurt badly or die. Then what is the point ? The whole life, every second is risk assessment, decision and action. Otherwise, you may sit in your house safe and sound and wait to die by natural cause, earthquake, could rob you, kill you or a plane could hit your house...Honestly, your approach keeping out information that you studding chemistry and asking at first such banal questions with false conclusions, then revealing yourself as an expert in chemistry and self answering is not proper way at all.Always keep in mind that many actual beginners read this!And many of them are not capable yet to "digest" or distinguish what is really important and what not in handling HCl. For them it is the best approach the safest way (ordering finished PCBs or at least using Ferric Chloride).QuoteMaximum safety, well educated about the matter and maximum attention is the key when handle hazardous materials, especially for hobbyists. Let review briefly my own "fails" experience in electronic as a hobbyist:When started, I have blow up some fuses, LEDs, burned some resistors, ICs, short it, etc... - all in controlled experiments and low voltage circuits.Accidents: I had I or II degree burnt from iron when started SMD soldering under magnified glass (nothing serious, just briefly tip of iron touch), slip few drops on Cupric Chloride on concrete when moved etched PCB to container with baking soda, few times inhale fumes from soldering, did inhale some HCl when prepare Cupric Chloride bath...Nothing serious really, but these "accidents" happens when I was over competent considering that all is completely under my control or had less attention - these mistakes may easily get quite worst... I'm still doing PCBs, repair my own devices... However, did not touch old CRT TV (even it is rich of parts may be quite useful), as I do not have tools to handle high voltage from cathode, power supplies, and similar...All according my current knowledge and practice as a hobbyist in electronic, I do not reach over my limits. In my profession however, I push myself out of limit all the time - that is called progress, doing as well other hobbies... Otherwise I would do some boring physical job whole my life all over again and nothing else.QuoteExactly the point here. Many beginners in etching reading this will now say: "Nah, some people here says to be extreme caution but other says HCl is a peace of sh... What a bunch of morons! I could do some pranks with my self, my brother/sister..."Well done!As well, there is many videos on Youtube move PCB right out of etchant (without neutralization) under tap water and right to the sink, actually they dump down the drain right away whole etchant without neutralization...You have also wrote:Quote from: Beamin on July 22, 2017, 08:48:04 amThen:Quote from: Beamin on August 14, 2017, 09:29:27 pm"Ferric Chloride seems to be the best chemical except for its not safe to dump down the drain but I can manage safe disposal" Then: "HCl produce no toxic waste" ?!And then you claim you studying chemistry and self answering claiming that you love to shock people?All that is absolutely irresponsible from you - there is no pranks with extremely hazardous materials, especially with other people may get all that as granted.If that is true, you must be in early 20's and do not know strict laws regulative about handling hazardous material. BTW, I could be your father by age.

author: tggzzz
author_rank: Super Contributor
timestamp: August 25, 2017, 10:22:16 am
content: Quote from: sasa on August 25, 2017, 08:39:44 amMy motto, one of three that are worth remembering, is "trust, but verify". That implies you know what ought to be done.QuoteI think the word "maximum" is being used in different meanings. Despite claiming that "maximum safety" is key, you actually avoid maximum safety - because you do things that have a noticeable risk! (Quite sensibly in my view).Overall I don't think "maximum safety" is a helpful concept; it sounds too much like an unattainable slogan. OTOH "appropriate safety" is a much moreusableconcept, because it acknowledges both risks and rewards.

author: Zero999
author_rank: Super Contributor
timestamp: August 25, 2017, 10:37:49 am
content: Quote from: Beamin on August 25, 2017, 12:30:59 amI'm sure that was not your attention, but asking new be questions, then revealing you know it all, could be seenas trolling. Why ask the questions to start of with, if you already know the answers?If you want confirmation, then it's far better to state what you know and your reasoning and ask whether it's correct, rather than playing dumb. You are posting in a professional forum, not dealing with some dodgy salesman.

author: sasa
author_rank: Regular Contributor
timestamp: August 25, 2017, 02:45:11 pm
content: Quote from: tggzzz on August 24, 2017, 05:28:50 pmLook at this for instance, instead wrote answer (watched long time ago):

author: Buriedcode
author_rank: Super Contributor
timestamp: August 28, 2017, 11:32:31 am
content: Well that escalated quickly.Am I the only one who has avoided such issues by only ever using di-Sodium Peroxodisulphate?https://www.rapidonline.com/mega-electronics-fine-etch-clear-pcb-etchant-29448Unless one lives in the middle of nowhere and cannot order anything, then why bother with ferric chloride or homemade etchants at all? FeCl, as many here have stated is generally a nightmare in terms of usage and disposal. Homemade etchants might work, but you will have to experiment for best results, which uses up time.Seriously, just buy clear etchant. If you're into experiments and chemistry, use that knowledge to make a tinning solution, or effective additives for doing your own plated-through-holes, but fannying about with etchants when there are relatively cheap and easy pre-made solutions available is just wasting time.

author: janoc
author_rank: Super Contributor
timestamp: August 28, 2017, 03:33:36 pm
content: Quote from: Buriedcode on August 28, 2017, 11:32:31 amThat is only a different name for sodium persulfate, which has been mentioned several times in this thread. Along with the fact that while it is a good etchant, commonly used industrially, it is hardly an economic solution for a hobbyist making one board every once in a while. The solution is unstable and decomposes quickly, so it will go bad rapidly if stored (shell life about 2 months).Moreover, storing it produces oxygen gas, so it needs to be stored either in a special bottle or with the stopper not put on tight, otherwise the bottle may burst or eject the stopper -> risk of spilling it.It also doesn't really etch unless warm to 40-50 C, so an extra problem to deal with unless you have a heated etching tank.Re toxicity - about the same as ferric chloride, you will get heavy metal compounds in the result. Doesn't need to be neutralized (neither ferric chloride, btw), it forms only weakly acidic solution. Neutralizing it won't do any harm, though. However, you still can't simply pour the spent etchant down the drain, even after dilution! It is still considered dangerous waste. And unlike ferric chloride that can be regenerated/reused, you will be producing quite a bit of waste with persulfate.Also the powdered stuff you buy is a strong oxidizer that can cause fires or even explosions if it gets in contact with a suitable materials - e.g. powdered metal or even paper can be enough. Ouch!I have tried it but quickly went back to ferric chloride - persulfate is for low volume home board etching just more trouble than it is worth, IMHO. If you are making several boards every week, then it could be different but that's not that common for a hobbyist, especially a beginner.

author: Beamin
author_rank: Super Contributor
timestamp: August 28, 2017, 06:26:01 pm
content: Quote from: sasa on August 25, 2017, 08:39:44 amWho said anything about pranks or shocking people? I was never one for pranks even when I was in my 20's. When I say no toxic waste I mean that you can just dump it down the drain without putting environmental copper compound toxins in the sewer system. I said ferric chloride is best as in it gives you the best traces. What is the point of neutralizing the ph of HCl when it is diluted 1000 times? Unless you mean getting the copper out of solution. SO: I should mention before you dump the HCl it still has copper in solution and you have to precipitate out the copper and filter it off before dumping.Why would you do pranks with HCl after reading a post on making circuit boards? Am I missing something?

author: KL27x
author_rank: Super Contributor
timestamp: August 28, 2017, 08:05:26 pm
content: QuoteSo you are implying you can precipitate out the copper without neutralizing the acid? What copper compound are you making which is so insoluble at, say, pH<4 ?I'm curious.

author: Beamin
author_rank: Super Contributor
timestamp: August 28, 2017, 08:28:02 pm
content: Quote from: KL27x on August 28, 2017, 08:05:26 pmHonestly I haven't tried it yet. So far I just let the HCl evaporate on paper towels until the water is all gone and then just throw it in the trash. Most likely I would try to make copper sulfate crystals. My at home chemistry lab is waiting until I have a place where I can make a fume hood and won't have to worry about the acid destroying all metal in the room.

author: hermit
author_rank: Frequent Contributor
timestamp: August 29, 2017, 02:33:30 am
content: This thread derailed and crashed a long time ago. If you want to debate safety start another thread on that subject.

author: KL27x
author_rank: Super Contributor
timestamp: August 29, 2017, 03:19:34 am
content: Why start a new thread? How many trainwrecks do we need? There's actually a lot of good information in this thread, even if the signal to noise is pretty low. That's the end result in most of the internet, though.I found it curious that Beamin is trying to learn how to make a PCB, but he happens to already be an expert at etchant recovery/recycling/disposal, lol. This is something that I am still learning.I remember adding baking soda, IIRC, to some ferric, once. More or less just to see what would happen. Instead of iron and copper compounds precipitating out, it just made an icky brown hygroscopic gelatin that could not be strained.I never actually disposed of ferric. I just kept using it by adding HCl and using aeration. I eventually made a fresh batch of pure cupric, though, because the stain factor of the iron.Anymore, I just use cupric chloride. When I collect too much extra etchant, I just let it dry out in a pyrex baking dish and collect the green crystals. It should have has some scrap value for recycling the copper and/or use as dry CuCl2 for making etchant. But until I have 20 pounds of it, who cares? My initial batch of ferric tainted cupric dried out in mix of mostly green copper crystals on the bottom with orange-brown, sticky hygroscopic ferric bits at the peaks; it looked not unlike marijuana from far away. Anyhow, these crystals are all in plastic bags in a box, next to my jugs of extra etchant and HCl. I probably have a couple pints of it, maybe 1 or 2 lbs. Drying out a couple liters of excess etchant is a once every leap year thing, for me.A couple of uses I know, cupric chloride is used to treat wood for protection (I think from insects and snails). And it is also used to keep slugs out of vegetable gardens. I'm not really worried as to how to dispose of it. I keep it around in case it might be useful. For instance, if I ever wanted to ramp up to a bigger tank/etch setup, I would have the etchant, already.

author: janoc
author_rank: Super Contributor
timestamp: August 29, 2017, 10:17:51 pm
content: Quote from: Beamin on August 28, 2017, 06:26:01 pmAnd do you really want (or have means) to dilute it 1000x? That's quite a bit of water to mix in if you are using concentrated acid!Apart from precipitating the copper out of the solution there is also another reason for neutralization - it converts the compounds into something that is potentially less harmful when disposing of it.E.g. neutralizing hydrochloric acid with baking soda will produce a saline solution and carbon dioxide - both harmless substances that you can safely pour even down the drain, whereas doing that with even diluted acid is not a good idea (could slowly attack the piping, messes up the bacteria in the sewage treatment stations, etc.).Even if you are drying the solution out to dispose of it it is probably safer to have water evaporate than the acid - HCl fumes are no fun. So neutralizing it beforehand will help with that - it will fizz with carbon dioxide while the reaction is going but that's all. Then all you will be left with will be some salts that will crystallize out as the water evaporates and no aggressive fumes.

author: janoc
author_rank: Super Contributor
timestamp: August 29, 2017, 10:39:00 pm
content: Quote from: KL27x on August 29, 2017, 03:19:34 amYou need to dry it out, e.g. spill it on a tray covered with paper or filter it through a paper filter. Then let the water evaporate.The brown "gelatin" you got is ferric oxide - basically rust. Copper will form a copper carbonate which has greenish color, however the ferric oxide will likely be more visible so it will be tricky to see unless there is a large amount of cupric chloride in the solution.Another way to neutralize spent ferric/cupric chloride etchant would be to add aluminium shavings - that will precipitate metallic copper out of the solution. However, that could be more tricky to do - baking soda is easier to obtain than metals, plus powdered aluminium (not shavings) is a major fire hazard.

author: sasa
author_rank: Regular Contributor
timestamp: August 30, 2017, 01:19:09 am
content: Basic chemical reactions regarding Ferric/Cupric Chloride should be handy to know are following (not balanced):Fe + O2-> Fe2O3Fe + Cl2-> FeCl3Fe + HCl -> FeCl2+ H2FeCl2+ O2-> Fe2O3+ FeCl3FeCl2+ O2+ HCl -> FeCl3+ H2OCuCl2+ Cu -> 2 CuClCuCl + HCl + O2-> CuCl2+ H2OFeCl3+ Cu -> FeCl2+ CuClFeCl3+ CuCl -> FeCl2+ CuCl2CuCl2+ Fe -> FeCl2+ CuNeutralization:HCl + NaHCO3-> NaCl + H2O + CO2CuCl2+ NaHCO3-> CuCO3+ NaCl + H2O + CO2(CuCO3is insoluble in water)FeCl2+ NaHCO3-> FeCO3+ NaCl + H2O + CO2Attention:I'm not a chemist, thus upper may not be exact. I have collected them long time ago from various sources. Please post corrections if notice some problems with.

author: Beamin
author_rank: Super Contributor
timestamp: August 31, 2017, 11:54:32 am
content: Quote from: hermit on August 29, 2017, 02:33:30 amAgreed. Whats ironic if I made a video of myself getting hurt with acid everyone in this thread would want to watch it. Then say "I told you so".

author: sasa
author_rank: Regular Contributor
timestamp: August 31, 2017, 03:25:04 pm
content: Quote from: Beamin on August 31, 2017, 11:54:32 amAgain, you making wrong assumptions... Who sane will love to watch how you (or anyone else) getting hurt with acid?Quote from: Beamin on August 28, 2017, 06:26:01 pmAs already pointed:1. Many actual beginners read this - for them it is the best advice not to play with HCl as primary etchant. You did represent yourself as such...2. Some people and most of kids are quite irresponsible and their primary goal is to make pranks with themselves or others, regardless they are aware of deadly risks or not. But most of them will think twice if deadly risks is involved.As well, I doubt many people who use muriatic acid in domestic ever read and even understand fully what is wrote on the bottle...

author: janoc
author_rank: Super Contributor
timestamp: August 31, 2017, 07:40:16 pm
content: Quote from: sasa on August 31, 2017, 03:25:04 pmThe same people who post/watch videos on Youtube of people getting killed or maimed. Or crowds that ogle an accident, everyone with a phone in hand recording it, but nobody will help the people that are possibly dying there.Don't underestimate human egoism, stupidity and fascination with someone else getting hurt ...

author: sasa
author_rank: Regular Contributor
timestamp: September 01, 2017, 09:46:04 am
content: Quote from: janoc on August 31, 2017, 07:40:16 pmAnd in this thread these are all? I do not think so...QuoteCertainly I do not, as I commented already. All I wrote here is to prevent any inexperience and not well informed, especially absolute beginners in etching, to get hurt or kill himself or other, or do any other stupidity...But honestly, I'm a bit disappointed Beamin did not wrote or at least commented chemical reactions I have posted. Instead, he wrote this...

author: Beamin
author_rank: Super Contributor
timestamp: September 01, 2017, 10:59:59 pm
content: Quote from: sasa on September 01, 2017, 09:46:04 amI tend to click on the last page of a thread and often miss things.If you look up nile red's youtube channel you will see his "pouring acid on my hand video" as one of his most if not the most popular.I fell if someone asks a question and you know what you are talking about you should give them the most information you can. Its not the internets job to be a parent or baby sitter. I have read countless forums where someone gets something potentially dangerous like a laser or High voltage supply and people just write back: "I don't feel comfortable giving you that information" or "that's dangerous don't do it" with out explaining why its dangerous. Then the person who could be a stupid kid or a very responsible adult has no information to go off of and might make bad decisions. "But a young kid might be reading this forum!" Yes they might once again you are not responsible for them and if you really want to make sure they don't get hurt arm them with knowledge instead of lecturing or trying to talk them out of it which is going to up the forbidden fruit factor. The most fun I had when I was a kid was using the most dangerous things possible. I never got hurt or got my friends hurt. I was often the "Range safety officer". I was much smarter then my friends and I knew they were going to play with gun powder/chemicals and other things so instead of telling them NO! I would help them, explain how you could get hurt and if I didn't think they were smart enough to handle things I would do the most hazardous parts. In all the crazy stuff we did (for obvious reasons I won't elaborate because some things were illegal to posses or make) no one ever got hurt and no property was ever damaged (other then the things we were trying to destroy). I attribute this to my constantly reading the internet and learning about things. If I didn't have that resource I would have tried anyways and probably been badly hurt. I can think of more then one time when things could have gone terribly wrong but didn't because I had read where someone did it like "this" and ended up in the hospital, so we did it like "that" instead. For example I remember my friend would have accidentally got gun powder into some threads being screwed on and that would have ignited prematurely; killing them and all around us. Luckily someone had posted a story on the internet about that accident and I learned from it.

author: KL27x
author_rank: Super Contributor
timestamp: September 01, 2017, 11:08:30 pm
content: QuoteI have seen this. Yes, I have taken boards in/out of a horizontal etch tank without gloves, and it won't melt your skin off, lol. But repeated brief exposure will give you some painful hangnails!Is best to avoid direct contact as much as possible and immediately dilute/rinse after exposure. HCl will also burn holes right through a brand new cotton shirt in short order.Skin is pretty tough stuff. I was only half joking when I mentioned spilling it on your crotch. The mucous membranes of eyes/nose/mouth, as well as the ones below your belly button, are the bits that are not going to like direct contact even for a second.This thread prompted me to google hydrofluoric acid accidents. One of the more memorable ones was 2 guys filling a bucket by putting it on top of a stack of shipping crates so they could tip a 55 gallon drum of 70% HF acid into it. This is an example of what can happen trying to do something with the wrong equipment. The biggest accident I found was made by a couple of workers unloading a tanker truck of HF acid using compressed air, and skipping some safety procedures. A very unfortunate accident occurred partially because the chemist was extraordinarily tall. The hooded bench was too short for him, so he was sitting when he tipped over a small container of HF, which then spilled onto his thighs. The investigation also concluded that he would have had a better chance if he had more water available. The lab was equipped with a water hose, but the flow was rather low. 6L per minute, IIRC. If he had large bucket of water on hand, he might have lived.Of course HCl is much less of a danger. But even if it means saving a perfectly fine pair of jeans, or preventing yourself from stubbing a toe or pulling a muscle while running for the shower and/or getting out of your clothes in record time, having some basic stuff on hand can help prevent some wishful hindsight. And if people are willing to take such chances with HF acid for something as mundane as their job, I imagine there are plenty of people willing to take some liberties in order to get their very first board etched.

author: tooki
author_rank: Super Contributor
timestamp: September 02, 2017, 01:33:48 pm
content: Quote from: Beamin on September 01, 2017, 10:59:59 pmFYI, you should get in the habit of using the orange "NEW" buttons in the forum listings -- it takes you directly to the first unread post since your last visit to that thread.

author: Beamin
author_rank: Super Contributor
timestamp: September 02, 2017, 11:27:10 pm
content: Quote from: KL27x on September 01, 2017, 11:08:30 pmCotton is cellulose. I have never been able to dissolve it in HCl. Scweitzers reagent which contains copper will dissolve it. sulfuric will dehydrate the cotton burning holes.What makes HF dangerous is the fact fluorine reacts with calcium ions in your nerves. Its probably the most painful acid because it doesn't destroy the nerves. Its not as strong as HCl; you would think it would be stronger because fluorine is above Cl in the group and the trend goes up: HI then HBr then HCl but the valance electrons in F are too close to the nucleus. Also some acid don't fully dissociate ( turn the H into H+; hydronium) but some dissociate twice. Coke is bad for your teeth because phosphoric acid dissociates twice at two different pH's.

author: KL27x
author_rank: Super Contributor
timestamp: September 03, 2017, 01:40:23 am
content: QuoteI stand corrected. Tag on (replacement) shirt is all synthetic, lol.