PCB Etching  - Page 1
Forum section: electronics / projects

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 03, 2013, 08:46:40 pm
content: Hello guys im relatively new in electronics and i would like to start etching my own pcb's but i came to a problem. What ways are the most cheap and effective?Also another thing is the equipment.I do not have a laser printer nor a drill (but i can get one motor with drill bits from ebay it should work for drilling pcbs.)Also i no idea what chemicals should i use for etching and what kind of copper sheet should i use (because i heard there are many kinds of copper sheets)A good addition to all this would be if you suggest me a program to design the layout before i embed it to the copper sheet.Thank you.

author: Ferroto
author_rank: Frequent Contributor
timestamp: February 03, 2013, 09:49:21 pm
content: I use EagleCAD to layout PCB's and make schematics, there's a free version available with limited functionality. As for producing the PCB's themselves you might consider a place like PCBcart which will produce PCB's based on your layout and mail them to you. Some places will even populate the board with components.I don't know much about developing PCB's at home, I don't like working with dangerous chemicals.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 03, 2013, 11:02:13 pm
content: Quote from: Ferroto on February 03, 2013, 09:49:21 pmThanks I will order one ready maybe

author: ee851
author_rank: Regular Contributor
timestamp: February 04, 2013, 01:09:13 am
content: Hi Chris,I use EAGLECAD too - the price is right. I am sticking w/ version 5.12.0 as version 6.xx is supposedly buggy. Suggest you view the video calledPCB Etching Bath with Heater and Agitationathttp://www.pcbheaven.com/projectpages/It shows how it is done. Lots of other cool electronic projects on that website too.

author: notsob
author_rank: Frequent Contributor
timestamp: February 04, 2013, 02:00:15 am
content: Due to an avalanche of attacks on the site by 'hacker' type activity, PCBHeaven's forum has been shut down

author: nctnico
author_rank: Super Contributor
timestamp: February 04, 2013, 02:48:33 am
content: A few years ago I got a second hand spray etching machine. I use Ferric Chloride as an etchant. It works like a charm although you should keep it in a shed because Ferric Chloride stains cannot be removed and it is rather corrosive to metals. The plus side of using Ferric Chloride is that it can be re-activated by adding Hydrochloric acid which can be bought at any grocery store or pharmacy. So you don't end up with cans of worn out etchant.Here is a website (in Dutch) but the pictures speak for themselves:http://www.electronics.gompy.net/etsbak/index.htmlWith this machine it takes about 2 or 3 minutes to etch a PCB. Before that I used to have an immersion etching machine but that needed 20 minutes to etch a board. Foam etching is also a good method but it only works with Ferric Chloride intended for foam etching (thus without anti-foaming agents).

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 06:08:17 am
content: Thank you all i think that the ferric chloride is the best way to etch a PCB at home...... but how can i find it?

author: svofski
author_rank: Regular Contributor
timestamp: February 04, 2013, 09:07:08 am
content: Ferric Chloride should be available in electronics shops, expensive for small quantities (but rather conveniently packaged) — or in larger quantities at chemical suppliers. Unlike many alternative etchants, in a closed flask it lasts forever, don't hurry to throw away the solution after having etched your PCB.Laser printer+laminator is more expensive than photo resist method at first but in my experience faster to start, easier to use, you need fewer various items to get started (printer+laminator+shears+etchant) vs. (printer+translucent paper+UV exposure box+spray+dry box+resist developer+etchant), the process is less messy too. I never had any success with a clothes iron though, that's a waste of time in my opinion. Hmm for the resist method you're going to need a printer anyway. Don't buy an inkjet. Make sure you can get your money back on the laser printer purchase too, some of the newer ones are no good for PCB making due to poor tolerances in the mechanics, they're fine for office but for PCB you need some precision.

author: poorchava
author_rank: Super Contributor
timestamp: February 04, 2013, 10:02:16 am
content: I don't agree on toner transfer method having higher setup costs than photomask method. Used laser printer you can buy for $40, and laser printer is very useful/efficient for everyday use too (using old LaserJet 4000 myself - 12k pages for $15 toner refill). Cheap chinese laminator can be had new from supermarket for $7 or so (that's how much I pad for mine).For UV method you need exposure box, which can be quite expensive to build. Actually only way to get cost comparable to toner transfer is to get a miniature sun tanning gizmo. They typically have 4 UV tubes inside. If you want to go LED way you need to pay waaaay more. On top of that you need a developer, which is not necessarily cheap. UV-sensitive laminate is more expensive than normal one (or you have to buy UV-sensitive spray paint which adds cost too). You can use dry film (i.e. DuPont) but again: this adds cost and requires a laminator too.I would also advise against Ferric Chloride etchant. It underetches quite easily and it leaves terrible brown stains on pretty much everything. It is also opaque so it's hard to see etching progress without taking the board out from etchant. Sodium Persulfate is far better than chloride. It's translucent (transparent at first, turning blue when saturated with copper). It's kind of an industry standard to use that. Other option would be hydrochloric acid + hydrogen peroxide, but it needs to be used in well-ventilated area as it releases chlorine gas.

author: Niklas
author_rank: Frequent Contributor
timestamp: February 04, 2013, 10:12:51 am
content: I have used copper laminates precoated with photo resist sensitive to UV light. The pattern was printed onto a transparent plastic sheet using a laser printer. Make sure that the plastic sheets are made for laser printers as some sheets are just made for ink jet printers and will melt inside your laser printer.A cheap IKEA style photo frame, consisting of a tree fibre backing, a glass front and some metal clips to hold it togeter, was used to keep the patterned plastic sheet and the copper laminate in place during the UV light exposure. A sun tanning lamp or something similar can be used and the exposure time is something between 1 and 4 minutes depending on the photo resist. Protect your eyes and go to another room during the exposure.Developing the photo resist with sodium hydroxide (NaOH), commonly used to clean out water pipes, about a tablespoon dissolved in 1 liter of water. The exact amount has to be tested as different suppliers of precoated laminates has different thickness of the coating. The laminates I used took about a minute to develop and the UV exposed areas went clean and the pattern was dark red with a hint of brown. Use water to rinse of residues of the sodium hydroxide as it will neutralize the etching agent.If you can not get hold of etching powder, then use a mixture of 1 liter hot water (hot to the hand, but not boiling), 1 dl of hydrogen cloric acid (HCl) and 1 dl of Hydrogen peroxide 30%.Caution! Make sure to mix them in that order! The acid will mix better if it is poured into the water and the risk of splashes is less. The active etching agent is the hydrogen peroxide. Do the etching outdoors as the reaction will produce gases not so nice to breath in. The etching solution will also cause stains if spilled onto a kitchen sink made of stainless steel.

author: svofski
author_rank: Regular Contributor
timestamp: February 04, 2013, 10:51:31 am
content: Re: exposure box. I used to use UV lamp that can be bought in a regular hardware store, it looks like a CFL bulb except that it's almost black. I made a makeshift reflector for it from some foil. That and two thick, ~7mm thick sheets of plexiglas to hold the sandwich of papers/pcb tight under the light. Nothing too fancy or expensive about that, made some 20 boards that way. I know some people go at great lengths building their fancy exposure boxes with UV leds and auto-off timers and that's cool but it doesn't mean that they are really necessary.Laminator costed me slightly more than $7 however. I wouldn't advise buying a used laminator, they get dirty, the silicone rollers get deformed.

author: Thor-Arne
author_rank: Unknown
timestamp: February 04, 2013, 11:10:35 am
content: Hi.I useKiCadto design my boards, it's free and can be run on different OS.Also, take a look at thisthread.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 12:51:11 pm
content: Thank so much all of you!!! I would like to use the cheapest method and to be honest i did not understand everything you wrote and i am sorry for that.So the best etchant is or isnt the Ferric Chloride?Which is the easyest method to do it ?Can i use a normal inject printer?How can i use a laminator ?Thank you.

author: madires
author_rank: Super Contributor
timestamp: February 04, 2013, 01:20:45 pm
content: Quote from: poorchava on February 04, 2013, 10:02:16 am250g NaOH for around 5 or 6 Euros and you need 10g for 1l water. Lasts nearly forever :-)

author: madires
author_rank: Super Contributor
timestamp: February 04, 2013, 01:50:09 pm
content: Quote from: ChrisGreece52 on February 04, 2013, 12:51:11 pmEach one has its pros and cons. Most DIYers I know prefer sodium persulfate since it's transparent (you see what happens) and the risk of over-etching is quite low. Fe-III-Cl is fast if you got a special foam etching machine.QuoteIf you done some PCBs the method you've chosen becomes easy :-) Don't expect the first PCBs to be perfect.QuoteJust for the photo resist method and the inkjet has to print nice dark black lines and areas. You might need to experiment with ink saver mode and different transparent papers.QuoteIt's used for the toner transfer method to transfer the toner to the PCB. It's easier than using an iron (the one for ironing clothes).PS: If you drill holes I recommend a small machine with 20000rpm or more, a drill rig and special PCB drill bits. The cheap drill bits don't last long and break easily. I like the spear drill bits.

author: nctnico
author_rank: Super Contributor
timestamp: February 04, 2013, 01:56:39 pm
content: Quote from: madires on February 04, 2013, 01:20:45 pmIn my experience mixing developer is not easy and the temperature is also very critical. I buy pre-made developer and keep the developer and the PCB material at room temperature. You only need a little bit to develop a PCB so the pre made stuff also lasts a long time.

author: madires
author_rank: Super Contributor
timestamp: February 04, 2013, 03:10:31 pm
content: Quote from: nctnico on February 04, 2013, 01:56:39 pmReally? For years I simply take a HDPE bottle, fill in water, add the developer and give it some time to dissolve. The bottle for the NaOH pellets has to be airtight because NaOH is hygroscopic. And the reactivity of the caustic soda (the solution of NaOH in H2O) is decreased by oxygen over time. Right, developing the PCB at room temperature takes not longer than 30s. If it's colder nothing happens at all.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 06:41:40 pm
content: Quote from: madires on February 04, 2013, 01:50:09 pmFirst of all thank you.So i came to a conclusionsodium persulfate for best etchantinject printer with black thick linesIronA lot of experimentingQuestions. Is sodium persulfate as cheap as the ferric chloride?What do you mean by transparent paper for inject printers (i thought that these came only for laser printers)If i get a motor like thishttp://www.ebay.com/itm/12V-Small-PCB-Drill-Press-Drilling-With-0-8mm-Drill-Diameter-28mm-Motor-Diameter-/290717399541?pt=LH_DefaultDomain_0&hash=item43b01b79f5But with nice quality tips for drilling the holes on my pcb?And Can i use copper sheets like thosehttp://www.ebay.com/itm/NEW-Copper-Sheet-Metal-4-x4-022-16oz-24-gauge-Arts-Crafts-Jewelry-Hobbies-/330853853104?pt=LH_DefaultDomain_0&hash=item4d086d27b0] http://www.ebay.com/itm/NEW-Copper-Sheet-Metal-4-x4-022-16oz-24-gauge-Arts-Crafts-Jewelry-Hobbies-/330853853104?pt=LH_DefaultDomain_0&hash=item4d086d27b0 to embed my design on them ?Thank you.

author: svofski
author_rank: Regular Contributor
timestamp: February 04, 2013, 07:32:29 pm
content: Persulfate does not last, basicaly you have to mix a new one every time. And it produces a lot of cavitation which is not a problem with photoresist, but it easily removes toner resist.It's really easy to use ferric chloride. Find a flat plastic bottle, like from gin or something, cut the top from it. It will contain the etchant during the etching. Hang the board inside of it vertically on a thread and a pencil (or just throw it in). Place the flat bottle in a larger can, like a plastic jar from some paint, filled with freshly boiled water. The water bath will keep the temperature of etchant high and vertical position will make it easy for the etch products to precipitate down. Usually it takes ~10 minutes to etch a board like this, single or double sided.As for the dirty stuff: use latex gloves from the pharmacy. Do it away from where you eat, lay some newspapers on the floor, have lots of running water ready. It really helps to have a funnel to drain the solution back into a bottle where you'll keep it and some glass sticks for preparing the solution. Glass sticks are easy to clean. Some throwaway plastic tweezers to pick the board from the tank, although if you're using gloves there's no problem using fingers. Fresh spills on ceramic tiles and the such can be cleaned with just water and a sponge, just don't let them stay for more than a few seconds.

author: svofski
author_rank: Regular Contributor
timestamp: February 04, 2013, 07:38:13 pm
content: ah, also — NaOH is cheap but it's very sensitive to concentration and temperature. A little bit less and nothing happens, a little bit more or heaven forbid a nondissolved grain falls on a board and you have to start from the beginning. A specialized developer is only expensive if you buy it in a specialized place. If you buy sodium metasilicate from a chemical supplier it's cheap.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 08:03:58 pm
content: Thank you.so bottom line what would you suggest to me NaOH which you can get the consetration right easilly or ferric chloride?

author: baljemmett
author_rank: Unknown
timestamp: February 04, 2013, 08:12:00 pm
content: Quote from: ChrisGreece52 on February 04, 2013, 06:41:40 pmYou don't need the iron if you're using photoresist instead of toner transfer, and you can't use toner transfer with an inkjet printer, so make sure you've got which method you're using straight in your head before you start buying equipment!

author: nctnico
author_rank: Super Contributor
timestamp: February 04, 2013, 08:12:40 pm
content: One more thing about Ferric Chloride: when you buy it it is usually supplied as dry 'balls' in a bag. You'll need to add water to make etchant. It is extremely important that you use distilled water (for a car battery). Water from the tap contains too many polutants which will causes flocking of the Ferric Chloride.

author: madires
author_rank: Super Contributor
timestamp: February 04, 2013, 08:24:27 pm
content: Quote from: svofski on February 04, 2013, 07:32:29 pmUsually it lasts about a year for me (etching machine). Fe-III-Cl etches even at room temperature (foam etching around 45°C), sodium persulfate works best around 40-45°C.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 08:33:57 pm
content: Thanks guys but i cant store all these infoBut just suggest the best etching method for a beginner the most cheap to if this is possible.Thank you and i am sorry but i am getting more confused with all these.If you want me to understand please explain all the technique's for etching (or the 3 most popular if not all) the products each one uses and the process and tools it takes to etch a board.

author: madires
author_rank: Super Contributor
timestamp: February 04, 2013, 08:35:51 pm
content: Quote from: svofski on February 04, 2013, 07:38:13 pmYes, Na2SiO3 is easier to handle but I never had any problems with NaOH. If you follow the recipe everything works fine.

author: IanB
author_rank: Super Contributor
timestamp: February 04, 2013, 09:25:20 pm
content: Quote from: ChrisGreece52 on February 04, 2013, 08:33:57 pmAh, welcome to the world of learningWe can tell you things, but you will hold the information better if you research it yourself.Sit down in front of Google with a pen and a notebook, start looking things up, and make notes as you go. You need to organize and arrange all the facts and pieces of knowledge until the picture becomes clear in your mind. It is part of learning how to learn. Once you have the facts straight, you can make a choice about where to begin with your experiments.Expect your first experiments to fail. They normally will, and that too is part of learning. Try to figure out what caused the failures, go back and do more research if necessary, and try again until you succeed.One thing you will soon learn is there is no "best" answer to any question. There is only the answer that is best for you. Only you can figure out what will work best for you, and you will need knowledge and experimentation to help with that.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 09:30:16 pm
content: Thank you for this as Dave says In engineering Go ogle is you best friend. i will post the results and what i got from my research here thank you.

author: calin
author_rank: Regular Contributor
timestamp: February 04, 2013, 09:38:10 pm
content: Cheapest -1) laser printer / just not Brother because the brother toner fuses at a higher temperature the rest. Hp or Samsung is good2) Staples photo paper (or any decent glossy paper). You don't really need the fancy "laser transfer paper" - i use glossy paper from staples and work a treat (able to do 0.5 mm traces easily with a laminator - i even did 0.4 LQFP a few times) - 350 sheets was like 30$.3) Etching Solution : 1 part hidrocloric acid (pool acid also know as muriatic acid) (2.30$ at Ace Hardware) and 2 parts Hydrogen Peroxide 3% (like 1.50 at Wallgreens or even grocery stores or whatever pharmacy you find it). I do a very small fresh batch each time, it etches extremely fast - under one minute. Use a plastic brush and lightly brush the board while etching.4) Tap water5) Acetone and Comet cleaning/scrubing powder (i do not use any 3M scrubby stuff at is scratches too deep and thin traces will not transfer). Steal Comet from kitchen of course. Buy some acetone from Home Depot or Lowes not nail polish remover stuff, that is not working.Wash board with Comet, rinse well ... dont put your paws on the board !!Trick: Wipe the board with Acetone before toner transfer, the tiny bit of acetone that remains on the dried board does miracles with toner transfer. I noticed this by mistake and it a a pretty good "discovery"If you have a laminator for toner transfer great, if not steady hand and an clothes iron will work. For very thin traces you will need the laminator. The e-bay "drill press" is junk - I bought one and it spins very slow; too slow for PCB carbide drilling. Go ho harborfreight and buy one of their cheap rotary tools and you will be better off.And .. well patience and practice ...

author: Chasm
author_rank: Regular Contributor
timestamp: February 04, 2013, 09:58:00 pm
content: Scrubbing to remove the toner is a pain but for some toners (say OKI) pain thinner works really well.No scrubbing required, just soak the toner and rinse off after a while.The really nasty smelling stuff like Nitro usually work best - so better use it outside...If your toner does not stick chances are that the copper was not clean enough. Etching the board a little bit is usually the fastest method to remove oxides, grease and dirt. Just don't add new fingerprints.Also, try to use SMD instead of THT. After drilling the first board you'll know why.(Unless you have a really nice setup for the drill.)

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 10:07:04 pm
content: I gave it a little research and i think that ill go with the Photoresist method because it seems to be simple and fairly effective and cheap.Question can i print my own design on transparent paper or glossy paper and then have it embedded to my board or can i use a regular inject because i cant get a laser one now.I think that i will need to this processMaterials :1) This acid that you first place the board in (light "ferric Chloride" brown)2)ferric chloride3)glossy or transparent paper4)frame to put the board in to embed the design5)copper sheet6)UV lamp i saw that a regular one will work just fine.7)Container with lead8)Water (for the 2 rinses)9)marker (for any mistakes on the design)10) Gloves11)drill12)drill bit13)well ventilated space14)acetoneProcess1)Print /design the circuit2)Put Copper Sheet on the frame and expose it to UV light or a high power lamp3)etch with the other ferric chloride like thing4)rinse with water5)etch with ferric chloride6)rinse with water7)drill the holes8)clean the green thing with acetoneSource :I am aware that my PCB wont have solder mask or soldering pads.What can i do to add a solder mask to the board?Also i am sorry for the mistakes i made please correct me if i am wrong about the process or the materials needed.Thank you. I will continue my research of course.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 10:09:54 pm
content: Quote from: Chasm on February 04, 2013, 09:58:00 pmThanks for the advise and i will probably will go with the SMD components instead of though hole. Because ....I Dont have a drill i am thinking of buying a cheap one from ebay (that will be a motor (only) with a drill bit attached to it.)

author: IanB
author_rank: Super Contributor
timestamp: February 04, 2013, 10:29:17 pm
content: You didn't specifically mention it in your post, but you understand that for the photoresist method the copper clad board needs to be coated with light sensitive photoresist?There are two ways of doing this: you can buy the photoresist in a spray can and spray it on yourself, or you can buy the board already coated inside a black plastic envelope. Most people say that using the spray can makes it difficult to get even coverage and that much better results are obtained with the pre-coated board.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 04, 2013, 10:37:24 pm
content: No thank you for that i had no idea !!!!Thank youbut i could not find any pre coated and either could find a can o spray so i can coat them so for this i am asking your help ...

author: Thor-Arne
author_rank: Unknown
timestamp: February 04, 2013, 11:20:11 pm
content: There are 3 steps actually.Developing - This includes preparing the board with the photo resist, expose it, and then remove the unexposed photoresist.EtchingCleaning and drilling - This includes removing the leftover photoresist.This guy uses dry film photoresist, it requires you to have a laminator.Also, this method can be used to add soldermask and silkscreen.Free_electron summarizes the process very nicely in thispost.I suggest you read the whole thread as there is some other useful information there, including sources for materials.

author: nctnico
author_rank: Super Contributor
timestamp: February 04, 2013, 11:56:25 pm
content: I strongly recommend buying boards with photoresist (often called pre-sensitized) and use the UV exposure route. The problem with applying photoresist or using a laminator is that the copper must be very clean. Getting the UV exposure time right (which is different for each brand and sometimes even varies by type of board) is tricky enough.Although I must say I like the idea of using photoresist to add a solder mask to a PCB. I've got to try that.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 05, 2013, 09:02:20 am
content: Quote from: Thor-Arne on February 04, 2013, 11:20:11 pmThank you now i am gathering my supplies (at least get an idea of the items)http://www.ebay.com/itm/10-Photoresist-Dry-Film-developer-Resist-Remover-for-DIY-PCB-Photo-Etched-PE-/251108092794?pt=LH_DefaultDomain_0&hash=item3a77356b7aFilms and developer.!!!it also has instructions.

author: HeliEye
author_rank: Newbie
timestamp: February 06, 2013, 07:03:15 pm
content: Hi AllI've been producing in-house Prototype PCB's now for many moons.I do produce production pcb's in my work, but still find it Very useful to produce a quick prototype In-House.I have now settled for what I find will give me a high-res pcb in the shortest possible time...Basic kit I use :- (Supplier link/Data at the end)High resolution InkJet Film (A4 sheets, pack of 10)UV Box (4 tube) but less tubes still works.UV Pre-sensitised PCBUV Board developer, (concentrate, makes loads)Sodium Persulfate Etchant (The nice clear stuff, that looks like Salt before it's desolved/mixed with water)3x empty Ice cream tubs ( developer, water rinse, etchant)I produce all my artwork in Proteus (Isis & Ares)Once I have a final design, I print the Pcb on Hi-Res Inkjet film, on a standard Epson Inkjet (Photo R200) on highest detail settings possible.Expose the Positive for about 3 minutes in UV box.With an inch or so of developer in one of the ice cream tubs and with Latex gloves, rinse pcb in the developer, until the track image is clearly visible, rinse in the water in the 2nd icecream tub, check under magnification that all developed ok. (do this in 'subdued' light)Next, etching, I recommend warming up the etchant, I just do this in a microwave, hand warm is fine (I use in reality a large heated Bubble etch tank)But.... as we are trying to show that this is possible on the cheap, we need to get a little creative with just a ice cream tub.I use a spray-can plastic cap for this... I stick a double sided sticky pad to the top of the plastic cap, then stick the back of the pcb to the pad, turn up so pcb copper is facing down and floating in the etchant, giving the pcb a shake in the etchant every 10 seconds, it should be done in about 10 to 15 mins, depending on chemical strength and temp, I always make it slightly stronger and hit it with some heat (about 50c)Here's the link to where I buy all my PCB stuff >>Inkjet film Pt No 100-075http://www.megauk.com/artwork_films.phpPhoto Laminates (UV PCB)http://www.megauk.com/pcb_laminates.php4006V05 Seno Liquid Dev conc 1Ltr for 10Ltr - 20ltrshttp://www.megauk.com/pcb_chemicals.phpFine Etch Crystals to make 2 Litreshttp://www.megauk.com/pcb_chemicals.phpI didn't include developer stripper.. just use thinners/nail varnish remover or similar, pinch some of mums ;-)I appreciate that some of the above is going let you make more than you need, you could always split cost with a couple of mates?There is a lot of helpful info on the above site, so worth a poke around..#Note: I'm not affiliated in anyway to Megauk, it's just the only site I know that does Everything I need for pcb's.See pic of some Inkjet artwork, some Pic controlled project? forget which, plus a small etched pcb.. (all I had lying around)CheersSteve

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 06, 2013, 09:40:16 pm
content: Thank you !!! realy you got me what i needed excactly now i must buy the supplies and make my own etching shopAlso can i use 25 uv leds instead for UV tubes?

author: Psi
author_rank: Super Contributor
timestamp: February 08, 2013, 01:31:52 pm
content: Quote from: svofski on February 04, 2013, 07:32:29 pmyeah, I found out that the hard way.Persulfate sucks for toner transfer pcbs.Use FeCl. Or HCL+ peroxide (What i use) if you want something a bit safer to work with .

author: MrsR
author_rank: Regular Contributor
timestamp: February 08, 2013, 05:52:41 pm
content: Quote from: ChrisGreece52 on February 03, 2013, 08:46:40 pmGo for a positive resist and all you need is an ink Jet printer and UV source you can get CAD programs pretty cheap. Design Cad 2D $49 au works well.Rachael

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: February 08, 2013, 09:05:31 pm
content: Quote from: MrsR on February 08, 2013, 05:52:41 pmThank you i will give it a search.

author: Psi
author_rank: Super Contributor
timestamp: February 08, 2013, 11:51:57 pm
content: Quote from: Chasm on February 04, 2013, 09:58:00 pmAll the laser printers I've used for toner transfer have produced toner that dissolves pretty quick in turpentine and just wipes off.

author: mobile
author_rank: Newbie
timestamp: February 13, 2013, 04:20:15 am
content: I also use to etch the PCBs by myself, I use a 300 watt UV lamp (which is supposed for horses ^^).I can strongly recommend to not go for the toner transfer method, it's almost scam. I'm doing very small traces but only with the UV light method. The toner transfer method was never accurate enough over an entire PCB.The photo-positive PCB has been exposed to the UV light for around 5 minutes (that constantly gives the best result here).It's important that the foil has some good printing without holes on it (maybe go to a printer shop if your printer is not good enough).Better use Sodium persulfate so you can watch the PCB permanently and avoid over-etching, heat up the liquid to around 40-50 degree. As by my experience it's enough just to make the water circulate (a small pump for an aquarium should do).If etching is not quick enough I instantly add more Sodium persulfate to the circulating etching liquid, it always worked out safely.All the etching process should be done within 10 minutes.Ferric chloride is nothing but a big mess, after using 2 liters it's enough I'm not going to use it anymoreWhen it comes to disposal, I just use to get rid of most of the water inside (by heating it up and letting the water disappear) and give the rest to some special disposal company which in the end is cheaper than getting rid of Ferric chloride.All together I think I spent around 120$ for all the equipment.try to get a set like this one:http://www.ebay.com/itm/2set-PCB-Etching-Tank-ET-20-with-Agitator-and-Heater-2L-AC110-KinSten-Taiwan-/140750724417?pt=LH_DefaultDomain_0&hash=item20c5659d41

author: smashedProton
author_rank: Frequent Contributor
timestamp: February 13, 2013, 05:19:31 am
content: Can't you just dispose of etchants by adding in aluminium, then filtering out the copper and dumping it? Aluminium chloride isnt bad for the environment. You get the copper out too, bonus.An alternative is to add sodium carbonate. That reaction is a little less exothermic, but it produces gas