Etching at Home - Page 1
Forum section: electronics / general

author: Stiege
author_rank: Regular Contributor
timestamp: January 23, 2013, 07:40:58 pm
content: Currently for me to make a board I print onto Press n Peel PCB film:http://www.jaycar.co.nz/productView.asp?ID=HG9980&keywords=PCB&form=KEYWORDThen have to use my iron to transfer this to copper, and etch with ammonium persulphate.The end result has not been great. The heat transfer is probably the hard part when trying to use an iron to heat what can be a reasonable size board. Can someone suggest some better equipment?Cheers

author: smashedProton
author_rank: Frequent Contributor
timestamp: January 23, 2013, 07:48:58 pm
content: I etch boards!Using dry film is the best way to do it. If you are not getting good results, you should try cleaning the surface better, and by putting a high thread count sock over the iron.Your problem is probably your developer.. The best diy developer is a solution of sodium silicate (water glass) and sodium hydroxide. Hit up mikeelectricstuff's website for more info. He has done a wonderful job.The etchant that I use is ferric chloride. I know that it is terrible for the environment, but I know how to dispose of it properly. I make it myself so that i wont be ripped off by anyone. Take a jug of muriatic acid, and slowly react it with an excess iron in a pyrex container. Be careful of fumes. the youtube channel nurdrage has an excellent explaination. Good luck

author: alanb
author_rank: Frequent Contributor
timestamp: January 23, 2013, 07:56:27 pm
content: I have recently started to etch boards and have achieved good results.I use photo sensitive boards exposed through tracing paper. Then developed in Sodium Metasillicate and etched in Ferric Chloride.My light source is a standard low wattage CFL lamp.I can strongly recomend reading Mikeselectrical's PCB advice.

author: Stiege
author_rank: Regular Contributor
timestamp: January 23, 2013, 08:09:06 pm
content: Quote from: smashedProton on January 23, 2013, 07:48:58 pmSounds great, but with the Press N Peel there's no development required, I just heat transfer, and that seems to be the struggle, and then etch. Should I switch to dry film photo resist and get a UV light?The etching has gone well, I've used ferric chloride at university but the ammonium persulphate has worked well enough at home and is fine for me starting out with.Quote from: alanb on January 23, 2013, 07:56:27 pmYup, think i know where to go from here. Cheers everyone!

author: Alana
author_rank: Frequent Contributor
timestamp: January 23, 2013, 08:54:53 pm
content: I had problems with press and peeel technique as well until i realized few things.1. iron needs to be hot enough, at least 160-200 deg celsius and there need to be lots of pressure while pressing. I use small vice to hold my iron, hot surface to the top then i place board on it and printed layout on top. Then i use peace of cloth to apply pressure, literally rub each square cm of the board with considerable amount of pressure. Repeat 2-4 times.2. press and peel paper i'm using is lined with chalk  and this is prone to acid. If i have a big board or multiple boards at once i soak it in kichen vinegar for some time then peel it off under warm/hot water.3. board - if its new cleaning it with acetone or nitro laquer solvent is enough, if its older and its oxidized its better to clean it with sand paper, some guys even see sand paper as means of make bard more adhesive for toner used in press-peel mehod but i dont think its always needed.With practise - in my case 10 boards about 5x7cm i got repetable good results. But still - its wise to have permanent marker that is echant-resistant for small corrections.

author: member_xyz
author_rank: Contributor
timestamp: January 23, 2013, 10:29:44 pm
content: I have tried blue press n peel from jaycar and gave up due to inconsistently poor results and frustration.I have experimented a lot with laser ink toner transfer method. Eventually I found an inexpensive Fuji laser printer <$50, semi glossy paper and a laminator is giving me a much better and more consistent results. Brother laser ink toner is generally not good and you can find a lot of info on the net about ink toner transfer.Press n peel is expensive and sounds more professional but I could not get good results from it.Laminator is so much easier to use than iron with right ink toner, but will not work with press n peel.

author: Stiege
author_rank: Regular Contributor
timestamp: January 23, 2013, 10:50:01 pm
content: Quote from: member_xyz on January 23, 2013, 10:29:44 pmThanks for that, I'll look into laser toner transfer before I splash out on a UV setup.

author: Slothie
author_rank: Regular Contributor
timestamp: January 23, 2013, 10:53:45 pm
content: I'd +1 on the laminator idea too. While experimenting with the laser printer/photo paper technique I found that if you use an iron its hard to get the pressure right - not enough, it doesnt stick, too much & the toner spreads too much, and with larger boards its hard to get the coverage even. I got some OK results with the laminator using a thin cardboard sheet folded over to "envelope" the board to stop things moving & increase the laminator pressure. I really need to go back and finish my experiments because since then I've changed laser printers and so need to redo all my timings etc!!.I always lightly rub the laminate with a piece of Scotchbrite in all directions and then buff with a dry cloth to remove residue immediately before doing the toner transfer, Dont make any deep scratches or the toner will melt & run along them...I found an important factor with ammonium persulphate was to keep it hot! I stand the (plastic) bottle in a bowl of water at about 60 deg C to warm it through, and stand the etching tray in a bowl of water at a similar temp. It etches MUCH faster and you get better edges which makes getting fine detail easier. I imagine the same applies to Ferric Chloride too.BTW the best photo paper I found was some no-name stuff I got at the pound shop. The Kodak stuff I tried was almost impervious to water and impossible to soak off - the cheap stuff peeled of after only a few minutes in hot water leaving very little residue behind. I went back and bought all they had in case they never stock it again!!I've got some projects coming up with SMT so I might revisit this.....

author: Psi
author_rank: Super Contributor
timestamp: January 23, 2013, 11:07:59 pm
content: Quote from: member_xyz on January 23, 2013, 10:29:44 pmReally? i've had pretty good success using blue press n peel from jaycar.- Ya need a printer which can do nice dark blacks.- Make sure the sheet cant move while you iron it. I make it larger than needed and superglue two corners.- I put the pcb on a sheet of cork 5mm thick. Then the press n peel blue goes on, then two sheets white paper on top.- Press with reasonable force on the iron (but not crazy) and vary the force direction (the iron surface wont be perfectly flat)- When your done keep the iron on the work and switch it off at the wall to wait for it to cool down. If you try and take it off while its hot you'll just smudge it.- Once it's cool peal the stuff off slowly on a diagonally axis. Roll it off so it only separates one bit at a time.eg--> use finger to roll it off______[__blue sheet_____----pcb--------------------------- I use FeCl or HCL+peroxide to etch.I did try ammonium persulphate once but its no good for press-n-peel.Ammonium persulphate needs to be VERY hot to work and the heat will make the toner and press-n-peel separate from the pcb during the etch.I did this TQFP with press n peel blue.It pushed the stuff a bit far (few breaks that needed pen touchup) but it did work well enough to use.

author: nukie
author_rank: Frequent Contributor
timestamp: January 24, 2013, 12:09:06 am
content: Toner transfer has been a try and try again for me since day one. The ironing is fine I manage to persuade my wife she needs a new iron so I can 'own' the old one for PCB work. The temperature dial is set permanently, and I always place a piece of cotton on the Pulsar TTS paper in between the iron, I suspect that it helps even out edges. I let the weight of the iron do the work, sometimes I apply a little pressure, too much means squashed tracks no good.The problem with my printer is in consistency. I can see certain parts of the thin tracks very dark and if there a fill or a thick track these area seems to be light and pitting occurs when I etch. Toner save is off and density is set to darkest ever. It's a windows 2000 era Canon laser printer.So I might just try the DuPont Riston dry film next time I make a PCB hopefully it will provide good results.tapatalk

author: Moshly
author_rank: Regular Contributor
timestamp: January 24, 2013, 01:26:08 am
content: Hi, I use the pulsar method outlined here ->http://ultrakeet.com.au/write-ups/makepcbsApparently you can use the press 'n' peel instead of the transfer paper and green foil. (I haven't tried it) I find that ferric chloride gives the best results (straight edges). Let your laminator heat up for 1/2 hour. I have found large PCB's sink allot of heat and may get too cool by the time the trailing edge gets to the heater. You can try feeding it back again but this causes another problem, the thermal expansion characteristic of the transfer paper and the PCB do not match and the far edge (print) may lift. After you've transferred the toner (using toner transfer paper) make sure all the gum is washed from the board (can cause blotches, green foil sticks to it or it prevents the foil sticking to the toner). I rinse the PCB under warm tap water gently running my finger over the board until my finger starts to grip the toner. After the application of green foil step use masking tape to dab over the board to remove any excess. Make sure your blank PCB is clean of oils, I find cleaning with very fine wet & dry sandpaper and soap & water. Make sure the blank PCB and the print is free of dust when you apply the print.ExampleBad.jpg : Defects caused by dust, note the pitting (bubbles) using Ammonium Persulphate.All other pictures etched with Ferric Chloride, the A605 PCB took a long time, fixed a few open/short circuits during the process, after etching i had 3 shorts and 1 open circuit. I think this is probably the limit for home made PCB's, from memory its 6mil/6mil.Used - Xerox Phaser 3125N & Modified GBC H65

author: Stiege
author_rank: Regular Contributor
timestamp: January 24, 2013, 01:55:51 am
content: Thanks, that's some great pr0n. Very impressive.

author: JoeyP
author_rank: Frequent Contributor
timestamp: January 24, 2013, 03:19:35 am
content: If you have access to a flat-bed plotter, and if your CAD package can output in a format the plotter can use, you can plot the artwork directly onto bare copper. Just etch with ferric chloride and clean with acetone. Plate if desired.About 25 years ago I started using my Roland DXY990 plotter and got very good repeatable results. Good enough that I made a dozen PCBs for a small run commercial product. Off-the-shelf felt-tipped pens worked fine. I found that the color of the pen made a surprisingly big difference in the result. For some reason, red worked best. You can often buy those Roland plotters on ebay for around $100 or less.For touch-up, off-the-shelf Sharpy pens used to work very well - better than the expensive touch-up pens available at the time. I don't know if they've changed their chemistry, I haven't made any PCBs at home in years.

author: MetraCollector
author_rank: Regular Contributor
timestamp: January 24, 2013, 08:01:34 am
content: Gentlemen, did you heard about alkaline etching ?It is the main way of etching boards in industry widely spread.http://www.chemcut.net/downloads/alkaline-etch-process.pdfI use it at home, my friend gave me some introduction through this article :http://svetelektro.com/clanky/alkalicke-leptanie-dps-532.html- sorry, slovak language, you can translate it:http://translate.google.sk/translate?sl=auto&tl=en&js=n&prev=_t&hl=sk&ie=UTF-8&eotf=1&u=http%3A%2F%2Fsvetelektro.com%2Fclanky%2Falkalicke-leptanie-dps-532.htmlGood luck, it is very good at home because of non corosive behaviour and all things considered, use of the solution is unlimited.

author: GK
author_rank: Super Contributor
timestamp: January 24, 2013, 09:00:52 am
content: Does anyone still use the UV method? My stock of inkjet transparencies is running out and the stationary warehouse I bought the last batch from doesn't seem to stock them anymore. In fact nobody seems to stock them anymore. Anyone know a reliable source?EDIT: Never mind, Kalex Electronics is now (finally) selling a suitable alternative product:http://www.kalexelectronics.com.au/polyester-artwork-base/Some might find that useful to know, I guess.

author: madires
author_rank: Super Contributor
timestamp: January 24, 2013, 11:47:44 am
content: Quote from: GK on January 24, 2013, 09:00:52 amYes, I'm using a laser printer and transparent drawing paper (tracing paper). That's inexpensive and works great. BTW, disable the "toner saver mode" for printing the layouts to get nice black traces and areas.

author: ptricks
author_rank: Frequent Contributor
timestamp: January 24, 2013, 11:52:18 am
content: I have tried every method available for DIY PCB. The best detail you can get is going to be with the photo method. The toner transfer method works but I highly recommend buying a laminator, I did boards with the iron method and it is not the way to do this, it can get too hot, pressure is uneven. One trick I learned for toner transfer is, after cleaning the PCB, drop the board in etchant until you see a solid color across the board surface, once I started using the etchant rinse before transfer I never had problems getting the toner to stick and it worked for everything from normal printer paper to magazine paper. One tip for those that have a hot air station, after you do the transfer you can go over the PCB with the hot air and heat up the toner and it will melt and fill in any of those speckled spots you might sometimes see.

author: GK
author_rank: Super Contributor
timestamp: January 24, 2013, 12:09:49 pm
content: Quote from: madires on January 24, 2013, 11:47:44 amHmmm..... I'm not not sure if my Epson inkjet would print successfully to tracing paper.

author: smashedProton
author_rank: Frequent Contributor
timestamp: January 24, 2013, 03:44:31 pm
content: I'm interested to hear about laminatiors. I laminate by hand with less than ideal results.

author: (In)Sanity
author_rank: Regular Contributor
timestamp: January 25, 2013, 04:19:47 am
content: I'm still stuck on the laser toner iron on method. I've been able to produce 5 mil traces with no issues at all. Double sided boards can be a bit tricky however. I've been thinking more and more about finding some other cost effective methods. PCB's really cramp my design ambitions. If it wasn't for having to make them I would have thousands of circuits built up and running. I had a really nice in circuit ESR meter fine tuned that even worked on batteries...only to have it never leave the breadboard. Part of the game I guess.Jeff

author: ptricks
author_rank: Frequent Contributor
timestamp: January 25, 2013, 01:08:53 pm
content: Quote from: smashedProton on January 24, 2013, 03:44:31 pmThe laminator I use is a scotch branded TL901, I didn't have to modify anything to use it and I use boards that are in the .060 to .090 range , it also is a double roller , top and bottom heater unit so heat flow is on both sides not just one like some of the cheaper models.http://www.amazon.com/Scotch-Thermal-Laminator-Roller-TL901/dp/B0010JEJPC

author: MetraCollector
author_rank: Regular Contributor
timestamp: January 25, 2013, 01:27:47 pm
content: Mmm, my hint about alkaline etching was untouched.But it is really a good method.Who of you are capable to do a solder mask at home either ?For few last years, I have put in home-made PCBs amount of money equalling value of multipling by 4 or 5 of value of PCBs I made.It is some kind of passion, making them at home.Sorry about quality of copper traces in sample, but I forgot it in the solution of H2O2, H2O, HCl

author: (In)Sanity
author_rank: Regular Contributor
timestamp: January 25, 2013, 01:42:36 pm
content: This is an interesting little how to.http://www.instructables.com/id/Toner-transfer-no-soak-high-quality-double-sided/#intro

author: (In)Sanity
author_rank: Regular Contributor
timestamp: January 25, 2013, 01:48:08 pm
content: Quote from: MetraCollector on January 25, 2013, 01:27:47 pmI would love to be able to make pro looking boards at home. Half the time I do at least one thing wrong and end up with a bodge wire. So it would be nice to just make a new board to correct for any issues. If I send them away to get made I still end up with that one issue. Via's are a bit of a pain, but not the end of the world. I just make sure I don't route a via under a chip and then just use a pass thru wire. Bit annoying..but it works.Jeff

author: Harvs
author_rank: Super Contributor
timestamp: January 25, 2013, 02:41:25 pm
content: I've tried and tried with the PnP blue over the years. I've never got decent repeatable results. However, one thing I've noticed is I get wildly varying results depending on the printer used. From pretty good to zero transfer at all. So I wonder if the large variation people have in success has something to do with which printer/toner is used.

author: (In)Sanity
author_rank: Regular Contributor
timestamp: January 25, 2013, 03:13:41 pm
content: Quote from: Harvs on January 25, 2013, 02:41:25 pmWithout a doubt, the printer and brand of toner is critical. So far I've had the best results with Konica/Minolta toner. Now if I can just keep their printers running I'll be happier.

author: Alana
author_rank: Frequent Contributor
timestamp: January 25, 2013, 06:36:50 pm
content: Quote from: (In)Sanity on January 25, 2013, 04:19:47 amI did 2 sides with toner transfer - trick is to have common line between boards - i managed by cutting my board so that one of the edges was exactly the edge of ready pcb. This is unadvised with toner-transfer but allowed me to make both sides match.Another thing is - i may use drilled holes as "fedushals" to match top and bottom. Basically - most of child-thinking ideas will work.

author: ptricks
author_rank: Frequent Contributor
timestamp: January 25, 2013, 09:11:51 pm
content: The printer I currently use is an HP laserjet 2100 that replaced my laserjet 4. They are really old printers but do a superb job at printing. Caution, they do weight a lot as they contain lots of metal, that stuff that existed before all the plastic they use nowThe one I have was made in 1998, has printed 900,000 pages and still works fine, I bought it on ebay, shipped for $40I think the problem some are having with using an iron is the iron can be too hot and you cannot get enough even pressure.With the laminator if the board is cold you need to warm it up doing multiple passes through the laminator with the sheet on it till you notice it start to stick, then do it a couple more times, the board will become too hot to hold so use a towel or cloth to hold the board. I run it through about 6 or 7 times turning the board each time. Might seem like a lot of time, but it really only takes a couple minutes.For double sided boards I apply the first toner sheet to one sideRun the board through the laminatorRemove the paperDrill 3 holes that will be used to line up with the second side of the boardAlign second side of paper with the holes while holding the board over a lightRun the second side through the laminator, the toner already on the first side will not come off, the rollers are a special type of rubber that is non stick.Remove the paper and etch. The holes are so small that over etching doesn't occur.

author: Psi
author_rank: Super Contributor
timestamp: January 25, 2013, 11:46:13 pm
content: Quote from: (In)Sanity on January 25, 2013, 04:19:47 amYeah.I've done it a couple of times and this is how i do it.1 ) Toner transfer and etch one side (cover the copper on the other side with insulation tape. Be careful to make sure there are no ripples in the tape on the edges)2 ) Drill out one through hole pad on each side of the pcb with the smallest drill you have. Make it as centered as possible, if you don't like the centering move to another hole and repeat.3 ) Print out the toner transfer sheet for the 2nd side4 ) With a sharp point puncher the sheet in the center of the matching pads5 ) Put the pcb and sheet together using two drill bits or two bits of rigid wire as alignment pins to match up the sides.6 ) Apply some super glue on the edges and when dry remove the alignment bits from step 57 ) Use Iron or laminator to transfer pattern to pcb.8 ) Mask off the already etched side and etch the new side.Note, you can etch both sides at once, but you need to be vary careful not to scratch the toner tracks when doing the other side. It's also harder with the alignment pins since you have to align both toner sheets at once.Note, you need to mirror image one side so check this is correct before you start. (your pcb package may/maynot already do it)

author: SgtRock
author_rank: Unknown
timestamp: January 26, 2013, 12:39:41 am
content: Greetings EEVBees:--At one time I was contemplating making my own PCBs, but I have been too busy doing repairs on friends stuff and dumpster finds. But I did to a lot of research and found the 4 part series of videos in the below link, which I believe to be the cleanest, best and most efficient approach to Homemade PCBs I have yet seen.http://www.getlofi.com/?p=1997--Please, any and all, have a look and tell us what you think." 'Tis a lesson you should heed:Try, try, try again.If at first you don't succeed,Try, try, try again. "William Edward Hickson 1803 - 1870Best RegardsClear Ether

author: free_electron
author_rank: Super Contributor
timestamp: January 26, 2013, 01:57:10 am
content: Quote from: Psi on January 23, 2013, 11:07:59 pmTry Sodium Persulphate instead. that's what the industry uses

author: Harvs
author_rank: Super Contributor
timestamp: January 26, 2013, 02:05:29 pm
content: After reading this yesterday, I though I'd have another go.Just want to say thanks. After using a few of the techniques people talked about here, I've produced two small boards with PnP blue that turned out spot on. I've never had that work like that before.I think the biggest factor was pre-etching the boards. The surface texture changes considerably and the toner/PnP stuck great.

author: ee851
author_rank: Regular Contributor
timestamp: January 26, 2013, 06:06:18 pm
content: wilfred, thank you for the tips.Quote from: ptricks on January 24, 2013, 11:52:18 amptricks, could you please elaborate on what you mean by this?I am a newbie at toner transfer and don't understand.This is on a cleaned copper-clad boardbeforetoner transfer, right? What etchant are you using?

author: smashedProton
author_rank: Frequent Contributor
timestamp: January 27, 2013, 06:41:58 am
content: He means that you dunk the board before you transfer toner. The theory is that it would roughen up the surface, so the toner would stick better. Hope this helped.

author: ee851
author_rank: Regular Contributor
timestamp: January 27, 2013, 04:53:51 pm
content: Yes, thank you. So if I dip the cleaned board in etchant, do I rinse the etchant off with water before applying toner? Or do I wipe it off with an oil-free towel?

author: SeanB
author_rank: Super Contributor
timestamp: January 27, 2013, 05:04:30 pm
content: Dip till an even matt appearance, then remove and rinse in clean water. Then dry with hot air, and do not touch it. Use surgical gloves and handle at the edges only. Apply toner within a few minutes or it will tarnish.

author: smashedProton
author_rank: Frequent Contributor
timestamp: January 27, 2013, 05:11:53 pm
content: Do any of you guys tin/ solder plate your boards? I have been looking into it, but A i cannot afford to buy the tin plating solution and B i do not know how to make it myself. I was able to scavenge a giant bar of 63/37 solder one time. I wonder if sulfuric acid and heat would do the trick...Is plating necessary for surface mount work? Or can I get away with soldering the components directly after the board is done?

author: (In)Sanity
author_rank: Regular Contributor
timestamp: January 27, 2013, 06:25:27 pm
content: Quote from: smashedProton on January 27, 2013, 05:11:53 pmIf the board is well cleaned before you start to solder with something slightly abrasive and some alcohol then you'll be good. The trick to SMD is using flux, without it your fighting a loosing battle. Even regular paper can be used as an abrasive. Cleaning and Flux are important parts.

author: ptricks
author_rank: Frequent Contributor
timestamp: January 29, 2013, 03:12:06 pm
content: Dipping the boards in etchant is really an important step. I first tried using things like brasso that are chemical copper cleaners and while they do make it look better they don't leave the copper with a surface that the sticks to the toner. My steps are:Clean the board with a little soap and water.Rinse well.Apply the chemical cleaner, like Brasso.Rinse well.Drop board in toner until even color across the board, if you see patches or spots that don't clear up then clean the board again. It can sometimes take a full minute for the board to get an even color. Depends on the etchant, I use mutiatic acid and peroxide.A quick note about the etchant . You don't have to keep making new etchant. The batch I am using is several months old and has etched a lot of boards. When you are done etching, place the container in a safe area where nobody will contact it , with the lid OFF. In a few days you will see the etchant return to the orginal light green color vs the dark green. I don't know the exact cause for this but assume it is the liquid being exposed to air . The more the etchant has been used the longer it takes to return to the light color.If etchant gets to the point where it can't be re-used you can do a couple things with it. One is plate out the copper, basically need a metal that can be plated with copper and a small voltage source, even 1.5V AA cells will work. In solutions where there is a lot of copper just placing another metal in the solution will cause the copper to attach itself.WARNING:DO NOT PUT ALUMINUM IN THE ETCHANT. IT WILL REACT VIOLENTLY.The reaction is toxic and can cause the etchant to reach temperatures that will melt a plastic container.If you want to store the etchant you can convert it to crystals that can be restored by adding some more acid. To make crystals place the etchant on a heat source of low heat and evaporate out all the liquids.

author: (In)Sanity
author_rank: Regular Contributor
timestamp: January 29, 2013, 03:53:30 pm
content: I just use a mild scotchbrite followed by a good scrub with acetone. I've never had toner not stick. I'm sure the toner has a lot to do with it.

author: Mark
author_rank: Frequent Contributor
timestamp: January 29, 2013, 06:17:49 pm
content: Quote from: smashedProton on January 27, 2013, 05:11:53 pmI used cold tin plating for my boards,http://www.rapidonline.com/Tools-Equipment/Tin-plating-crystals-2947590 grams will make 1 litre of solution, and it takes about 15-30 mins for the board to be plated. The tin thickness builds up the longer the board is left in the solution.I found it makes a difference to the way the solder flows around the connections and it doesn't tarnish or get fingerprints over time like bare copper does.

author: ptricks
author_rank: Frequent Contributor
timestamp: January 29, 2013, 07:16:09 pm
content: Something else you can use to keep the copper from tarnishing is a permanent marker, but I don't use the black sharpee brand ones. I use some colored markers that are sold cheap in packs of 6 colors. The colors are sort of useful because you can use the different colors to color code parts of the board by their function. The ink burns off when the trace is heated so no problem to remove.

author: Stiege
author_rank: Regular Contributor
timestamp: January 29, 2013, 08:23:37 pm
content: My laminator finally arrived, can't wait to give it a go!

author: Harvs
author_rank: Super Contributor
timestamp: January 30, 2013, 01:42:10 am
content: Quote from: ptricks on January 29, 2013, 03:12:06 pmSo are you saying that by plating out the copper it makes the enchant useful again?Or just that it's useful for when you want to copper plate something?

author: ptricks
author_rank: Frequent Contributor
timestamp: January 30, 2013, 12:39:03 pm
content: Quote from: Harvs on January 30, 2013, 01:42:10 amBoth.

author: GK
author_rank: Super Contributor
timestamp: January 30, 2013, 12:47:43 pm
content: Quote from: ptricks on January 29, 2013, 07:16:09 pmAnything wrong with solder-through conformable coating?

author: ptricks
author_rank: Frequent Contributor
timestamp: January 30, 2013, 01:53:44 pm
content: Quote from: GK on January 30, 2013, 12:47:43 pmDepends on what coating and what thickness. I use the markers because they are cheap, readily available , and easy to remove coating if needed.

author: GK
author_rank: Super Contributor
timestamp: January 30, 2013, 02:09:04 pm
content: Quote from: ptricks on January 30, 2013, 01:53:44 pmI mean the solder-through stuff specifically made for coating PCB's, such as this:http://au.element14.com/electrolube/cpl200h/lacquer-200ml-aerosol/dp/521462or this:http://www.jaycar.com.au/productView.asp?ID=NA1002After drilling I give the board a good rub down with steel wool (that gets rid of any tarnishing) then lacquer.Who knows what is in the can from Jaycar though. It might even be watered down with Samxon capacitor electrolyte.

author: notsob
author_rank: Frequent Contributor
timestamp: January 30, 2013, 02:55:03 pm
content: If you are trying to measure current and have high voltages, watch out for leakage.

author: ee851
author_rank: Regular Contributor
timestamp: January 30, 2013, 04:32:10 pm
content: Is that clear conformal-coating "lacquer" the same kind of "lacquer" used for waterproofing wood ?As an experiment, I cleaned four copper pennies with vinegar and salt to remove all oxidation, then rinsed them in tap water.I placed two pennies underneath an inch of distilled water in a plastic container. I sealed the plastic container with a plastic lid and put the other two pennies atop the plastic lid, exposed to air.After 117 days, none of the four pennies is as shiny as it was at the start. However, the ones immersed in water are shinier than the ones exposed to air--probably half to two-thirds are tarnished as the air-exposed pennies.So I plan to use Mark's "cold tin plating" on my etched boards.

author: smashedProton
author_rank: Frequent Contributor
timestamp: January 30, 2013, 11:52:21 pm
content: Gk, that's beautiful! Excellent work. A+

author: GK
author_rank: Super Contributor
timestamp: January 31, 2013, 03:09:26 am
content: Quote from: smashedProton on January 30, 2013, 11:52:21 pmThanks!Quote from: notsob on January 30, 2013, 02:55:03 pmAccording to the datasheet for the Electrolube CPL, the insulation resistance is 1 x 1012ohms/cm, though I guess the real figure would depend on how thickly you layer it on.http://www.farnell.com/datasheets/392349.pdfThere are more expensive coatings, such as the Electrolube HPA:http://www.farnell.com/datasheets/316960.pdf..... which has a quoted insulation resistance of 1 X 1014ohms/cm, but the cheaper stuff is quite fine for most applications.It's anyones guess as to what's in the can from Jaycar though.

author: nukie
author_rank: Frequent Contributor
timestamp: January 31, 2013, 12:16:17 pm
content: Quote from: GK on January 30, 2013, 12:47:43 pmThat's professional looking board. Does the coating gives off dangerous fumes?tapatalk

author: GK
author_rank: Super Contributor
timestamp: January 31, 2013, 01:04:47 pm
content: From the datasheet:"Can be soldered through without fear of highly toxic gases being produced (contains no isocyanates)."

author: nukie
author_rank: Frequent Contributor
timestamp: January 31, 2013, 02:51:47 pm
content: Quote from: GK on January 31, 2013, 01:04:47 pmIm going to keep that in my notes very useful thanks. Does the solder flow well with the coating melt mix?tapatalk

author: GK
author_rank: Super Contributor
timestamp: February 01, 2013, 09:43:55 am
content: Yeah, it's fine. So long as you don't layer on five coats you'd hardly notice it was there.