Etching your own PCBs

When [Adr1an] wrote in to share a link to his PCB etching tutorial he mentioned that he knew we had already covered a ton of these guides. He’s absolutely right, not only have we featured a great number of them, but we also wrote our own quite a while ago. But that doesn’t mean we ignore them when they come in on the tips line. In fact, we read all of them that have something to offer and are pleased to feature the ones that are well presented… like this one!

[Adr1an] went all out with his writeup. He not only covers all of the elements that go into this, but discusses where to purchase them and his thoughts on how he arrived at the choice. He’s using the toner transfer method and prefers Brother branded toner for its coverage and resistance to over-etching. He prints on HP Everday Photopaper, then uses a laminator to transfer to the copper clad board. For this guide he used 2oz copper but prefers 1oz copper as it etches faster. His etchant of choice is Ferric Chloride, which can be ordered as a dry powder. He uses the direct etch method of loading etchant into a sponge an applying that to the board.

The board he makes in the guide looks great, and it only took him 28 minutes!

Comments

  1. DeKay says:

    Great detail in this writeup.

    I’m thinking of getting into PCB fab at home but taking the inkjet route with this kit that was featured on HaD a couple years ago. Anybody have any experience with it?
    http://www.fullspectrumengineering.com/pcbinkjet.html#

    I like the idea of this approach because registration of double sided boards is bang on due to the tight tolerances of this setup. That and it looks like you can get to fine trace widths relatively easily. However in reading the Yahoo group for Homebrew PCBs using inkjets, it sounds like the process can be tricky to get right. I’d do this very low volume, so the time to do a board isn’t a deciding factor one way or the other.

    Thoughts?

  2. George Graves says:

    Start off using the toner transfer method. Then once you’ve perfected that, give the inkjet a go. Everything I’ve read about inkjet is that the results aren’t as good.

    Also, I have that laminator, and it’s just doesn’t get hot enough. You really need more heat to melt the toner then what it does for best results. You end up with flaky toner that isn’t fully melted to the copper. So there will be times that you’ll have lots of under cutting. A $15 walmart clothes iron works *much* better.

  3. Mulvane says:

    I’ve actually thought of doing something more cnc’ish and putting a inkjet type head on instead of a router and using that to paint the pcb and then having the plate submerge with the pcb on it.If the board fit into a clamp, doing double sided should be a cakewalk also.

  4. ltkenbo says:

    Good writeup, however the author instructs that you should print a mirror image of your artwork. This is only for the top layer (red in eagle). If you are doing a bottom layer (blue in eagle) it does not need to be a mirror image.

  5. Digitalundernet says:

    I’ve never been able to do this even using the SAME tools. My boards all come out like this http://digitalundernet.com/wp-content/uploads/2011/10/e0qDi1.jpg

    Thats the last board I tried to make

    • Microguy says:

      That looks close to what mine would have looked like, if I tried to etch it.

      To me, it looks like you have too much pressure in places, and not enough heat. (squeezing the toner out, and not sticking).

      i never got to that point, none of mine looked like they were worth even trying to etch.

      Check out MG Chemicals.
      http://www.mgchemicals.com/products/prototype.html

      They even had a plated through hole kit aimed at the hobbyist at one point, not sure if they still do or not.

      Print one or two transparencies, clamp it in two sheets of polycarbonate (perspex or whatever), since it’s not UV, glass panes should work.

      Expose with regular fluorescent lamp, develop with lye, and etch. I use muriatic acid (from Home Depot) and hydrogen peroxide.

      Piece of Cake.

    • Digitalundernet: Here is my latest: http://www.rouvali.com/fileadmin/Kuvia/IMG_0911.JPG.
      Done with HP semi-glossy inkjet paper, HP Color laserjet and clothes iron.
      How long yours took to etch? You should go under 30 minutes. If not, make stronger Ferric Chloride. Also, you can heat the Ferric Chloride to make it work faster(Submersible Aquarium Heater). Your traces are fading away and I think this could be caused by too long etch.. Are your traces solid when you start etching? If ink is not completely melted, you could melt it for good with heat gun, just before etching. I also see your traces get too wide. This could be bad paper or too much pressure(?) Also papers leave thin white layer of something on PCB, make sure you brush it out. Also before etching, use some sharp tool to remove ink/white stuff between traces. It is much easier than removing copper afterwards. Also what mark/model your printer is? I have seen comment that not all laser printers marks are good for this job.

      • Digitalundernet says:

        I used the HP photo paper that Adr1an talked about and I had a hell of a time getting the ink to transfer properly. It took about 30 minutes of work. I don’t have a laminator that the PCB’s can fit in so I used my clothes iron

  6. Microguy says:

    First of all, check out MG Chemicals pre-sensitized board. They can be exposed with regular fluorescent lamps.

    Second, you’re NOT supposed to clean a board with steel wool!!! It can leave tiny steel fibers embedded in the material. And if you end up wit h a short, it’ll take forever to find, and it can cause other nasty trouble shooting nightmares.

    Just use a good cleaner like “Bar Keepers Friend” (Found at most grocery stores, think, “Comet” cleaner).

    It’s got just enough abrasive in it, it’s mostly the citric acid that does the cleaning. Very little work, and you have a perfectly clean, smooth board.

    I could NEVER get the TTS system to work. I tried everything. I just about got to the point where I was going to “fix” the LASER printer so I just ran the board right though it, instead of transferring anything (it should work).

    But found MG Chemicals, and it was WAAAAY easier. Now I wish I hadn’t wasted so much time on the TTS.

    I know it works for some people, but man, a TOATL waste of time for me. (now I do perfect double sided board, piece of cake….) I shudder to think about a DS board with TTS.

    Nuts & Volts magazine had a write up about a thing called PCB FAB In A Box from Pulsar Pro FX.
    It looked like it did pretty good, but also looked like it may be a bit expensive. I don’t know.

    Basically, you get “special paper”. Then proceed almost normally. But you put it through the laminator one more time. But this time, you use “something” to “seal” the toner to the board.

    From the sound of it, you could use that regular toner “film”. I use it to add “silk screen” to my boards. Still can’t get the toner to stink well, but this works OK. You “iron” this film to the toner. For “silkscreen”, it’s white.

    http://www.pulsarprofx.com/
    http://www.pulsarprofx.com/decalpro/
    http://www.pcbfx.com/main_site/pages/start_here/overview.html

    It’s just decal film, you can get it in different colors, even metalized. It looks like they moved into the TTS stuff with this kit. I don’t remember it being out there before.

    My problem was getting a good enough TTS, I never got that, so this would never have worked for me. But if you get fairly good TTS, then this would seem like it would help out, if you get pin holes or something.

    Either way, nice stuff to have around. Front panels, Silkscreen, etc….

  7. truthspew says:

    Been etching my own for a long time now. Started when I was just a kid. Use the tank method for it and you can re-use the etchant.

  8. Someonecool says:
    • JohnBailey says:

      Because it’s readily available, cheap, and reasonably safe. There are also many many sites and books that show exactly how to use it.

      Not everybody can get hold of hydrogen peroxide at the required concentration. So not everybody can use the method detailed in the Instructable.
      The best I was able to find was about 5% hydrochloric, which turned the copper pink overnight.

    • Someonecool says:

      That is really weird. You don’t have a Lowe’s or home depot close by? Most hardware stores have this stuff.

      Sunnyside Muriatic Acid
      Quart
      Sku: 5613858
      Model: 71032
      $3.47
      HCI: 31%

      Sunnyside Muriatic Acid
      Gallon
      Sku: 5613845
      Model: 710G1
      $4.94
      HCI: 31%

      Green Envy Muriatic Acid
      Quart
      Sku: 5613859
      Model: 61032
      $3.49
      HCI: 20%

      Green Envy Muriatic Acid
      Gallon
      Sku: 5613846
      Model: 610G1
      $5.98
      HCI: 20%

      And at lowes:
      Klean-Strip 1-Gallon Safer Muriatic Acid
      Item #: 58558 | Model #:GKGM75006C
      $6.98
      No Info on HCI

      And At HD
      Smart 1-Gallon Muriatic Acid
      Model # 2118 HD
      Store SKU # 346289
      $10.92 a case
      HCI: 31.45%

      • Whatnot says:

        19 out of 20 people do not live in the US, and the EU and various EU countries have other rules on what is allowed to be sold, and then there’s the issue of somebody in your region supplying it and shops taking it into their inventory, sometimes it’s hard to get them to do it since the management can’t find/understand a reason so they refuse.

        And example of such things: I’m in the EU and noticed that they stopped selling epoxy lacquer everywhere in my area, it’s a bit annoying I can tell you, and I think it’s an EU directive since if they have it then it’s old stock that is sold until they run out.
        Oddly enough they do sell tons of stuff that is pre-painted with epoxy based lacquer, so I guess the solvents are dangerous while drying?
        Anyway in my area it’s also hard to get peroxide in any decent concentration, and it’s expensive, and peroxide has a short shelf-time when opened too.

      • JohnBailey says:

        Nope. Nor does anybody outside America. Perhaps Boots or B&Q?

        Although to be honest, I’m not too keen on storing HCL at home long term.

        I found a solution though. Peroxide, vinegar and salt. Thanks to an article here a few months ago.
        Not as fast as HCL perhaps, but doesn’t stain like ferric chloride, doesn’t give off much in the way of fumes, and is readily available pretty much globally, and although a bit slow, it does work quite nicely. Good enough for what I want to do at the moment at least.

      • Someonecool says:

        My apologies if I offended anyone or appeared like an arrogant american! :P

        I thought that something such as HCL in the form of Muriatic acid is a common item to find since it is used in pools and things like that and I don’t know of an alternative. I thought it is commonly found like vinegar or drain cleaning fluid.

        I have heard about using the peroxide, viniger, and salt combination as well!

      • Whatnot says:

        Nah nobody is offended here, well not by you, I am sometimes offended by the lack of materials available locally, there were times I needed a common item and then ended up going to 4 stores all over town to find they simply do not have it, it’s frustrating.

      • Whatnot says:

        incidentally, this is what they sell here as etching solution: http://en.wikipedia.org/wiki/Ammonium_persulfate

    • yamori says:

      I seem to remember being told that ferric chloride is safer to use than muriatic acid as it’s only corrosive to metals rather than biological material (something to do with ferric chloride not being a proton donor).

      I must admit my chemistry knowledge is pretty limited so I don’t know to what level that’s true, but it seems like discussion of the relative safety of different etchants is left out of the conversation quite often whenever I see people debating this. There’s more to it than just cost!

      And on that note, this guys tutorial mentions using powdered FeCl, which is probably bad advice for people learning how to etch their own boards as it can give off hydrogen chloride fumes when you dissolve it in water. Beginners are much better off sticking with the pre-prepared solution.

  9. Tom says:

    If one was gonna buy a second-hand printer specifically for this and not really for anything else, what would you get?

  10. koogar says:

    Ive been using Sodium Persulphate for all my etchings. The last time i used Ferric Chloride was about 20 years ago.Ferric seems overpriced in the UK and not as easy to get.

    It about £5 delivered off eBay for 1/2 Kg the mixture i use is 1 teaspoon for every 25ml of water.I then use a bain-marie method using a small tupperware container with the board in it and a roasting dish on the hob half full of water at around 50c.

  11. Joes Garage says:

    Thanks so much. I just got a free lazer printer from a friend that I repaired (just needed a good cleaning – haha on him) full of toner. PCBs are next! Keep up the great tutorials and comments. All you guys rock!

  12. cgimark says:

    A couple other tricks you can use:
    If you have a printer that is easily accessed when the toner cover is opened, like an old hp laserjet, if you time it right you can open the cover right after the toner has been applied to the paper but before it has entered the fuser and the opening of the cover will cause the printer to stop . Lift out the paper without touching it. The toner sticks right to the paper unless you rub it with a hand. Then just place is on the copper and heat and you get really good dark transfers.

    For cleaning the boards the best way I have found is wipe it clean of any oils or fingerprints with alcohol then dunk it in the etchant for a few seconds till it all turns a light pink. Rinse it with the alcohol then apply your paper and heat to transfer. Rinsing in etchant before you apply the toner seems to prep it better than anything I have seen.

    • Whatnot says:

      In another hackaday thread I was talking with a guy about that and he suggested to simply make a switch in the printer to disable or reduce the output of the heating element of the fuser, that seemed like a possibly simple hack to me and might work for people that have a printer that doesn’t play nice with the regular method, if for example yours uses toner that isn’t so great for transfer if it’s been through the full cycle.

  13. vic says:

    I’m using the photographic method because I haven’t been able to get good results with toner transfer. Getting the right temperature and pressure looks like a dark art.

    The best part however is using the sponge to etch the board; he says he managed to etch this board with only 5ml of ferric chloride, that’s impressive and all of it remains in the sponge in the end so that you can throw it away in the trash and avoid the problematic handling of copper ions pollutants.

  14. Ptolom says:

    I’ve done another PCB etching tutorial. It’s aimed at getting usable results really quick and cheap with hand drawn traces. I’ve since built myself a bubble tank, and there’s a new tutorial in the works for that.

  15. i tried Etching my own PCB once.Using cheap and easily available Projector Transperencies. http://murlidharshenoy.wordpress.com/2010/04/13/make-a-pcb-yourself/

  16. bootstrap says:

    Author has edited his page stating that he made a mistake when he posted saying he uses a Brother printer, in reality he uses a Samsung one.

  17. slinky says:

    One omission from this excellent write-up was noting which side of the HP Everyday Photo paper to use. I have had excellent results printing on the *back* side of the paper, and completely dismal results using the front side that one would normally print photos on. The main issue is the release stage. The back side releases better.

  18. Rusty says:

    Really liked the post, I got a lot good tips.

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