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I have tried several times, unsuccessfully, to manufacture a PCB at home. A lot of the other questions are about improving PCB performance and such, but I can rarely, if ever, even get the ink to adhere to the copper board. I even bought the special "blue" paper that I saw recommended several places.

What are some common gotchas that one might face when making a PCB? Specifically, I am having problems getting the ink to adhere to my board when I iron it. I have heard people briefly mention baking in the oven as an alternative.

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    \$\begingroup\$ What is motivating you to do it at home? With the free edition of EAGLE and typically less than $20 at BatchPCB you can get your board fabricated professionally... worth every penny in my experience :). \$\endgroup\$ – vicatcu Jul 6 '10 at 17:05
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    \$\begingroup\$ @vicatcu: The advantages for making PCBs at home: Much quicker. You can have it that same day, instead of waiting several weeks for BatchPCB. Much cheaper...a 4" x 6" copper clad board might be $5, the same PCB at BatchPCB would cost $70. Disadvantages: messy chemicals, quality wont be as great (eg, can't make quite as small traces), drilling lots of holes by hand is a pain. \$\endgroup\$ – davr Jul 6 '10 at 18:04
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    \$\begingroup\$ @davr, basically you're looking at about $2.50 per square inch + $10 shipping for a prototype. 4" x 6" is a preposterous size for a typical PCB. I recently had a 2.5" x 3.5" PCB made at BatchPCB and it cost me about $30 all said and done. My take is that if you are prototyping and your circuit is simple enough, do it on a breadboard; if your circuit is complex, its worth the saved time and frustration to have it fabbed at BatchPCB and wait 3 weeks to get it back. \$\endgroup\$ – vicatcu Jul 6 '10 at 20:38
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    \$\begingroup\$ My experience as a hobbyist is that there is a very high chance of messing up your first attempt at any particular board. (Oops I forgot to supply power to 2 chips, and none of my switches fit the holes drilled for them...) Then it takes another 3 weeks to get a fixed board.... \$\endgroup\$ – John Burton Jul 6 '10 at 23:29
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    \$\begingroup\$ I think making your own PCB is "one of those things you just have to do yourself", once or twice. \$\endgroup\$ – user1307 Jul 7 '10 at 1:20
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I use a home-made UV exposure unit with transparencies printed on an inkjet printer and pre-coated boards, and get excellent results - 8 mil tracks if necessary. I can make a PCB in 30 minutes or so, not including drilling the holes.

Here's a photo of my UV exposure unit, it's made from MDF and strips of wood. A sheet of glass sits on the wood strips at the top, of course. I left space for a third tube. I use an exposure time of 11 minutes.

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    \$\begingroup\$ how do you etch? \$\endgroup\$ – JustJeff Jul 6 '10 at 21:34
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    \$\begingroup\$ Ferric chloride in a small plastic container, in an old washing up bowl with about 1" of boiling water poured into it, to keep the etchant hot. With continuous agitation, etching takes about five minutes. \$\endgroup\$ – Leon Heller Jul 6 '10 at 21:57
  • \$\begingroup\$ I used to do it similarly but before inkjet printers, the transparencies were hand drawn \$\endgroup\$ – txwikinger Jul 7 '10 at 18:51
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    \$\begingroup\$ Do you have an opinion on that 'renewable' etchant? \$\endgroup\$ – JustJeff Jul 7 '10 at 21:03
  • \$\begingroup\$ Cupric chloride? I've tried something like it by regenerating ferric chloride etchant using hydrochloric acid and hydrogen peroxide. Over time, the iron disappears into the rinse water and it becomes cupric chloride. I found I could keep using it indefinitely, but it was quite a lot slower than reasonably fresh ferric chloride. \$\endgroup\$ – Leon Heller Jul 7 '10 at 23:22
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I've had a few people asking about the toner transfer method, so we made a video to explain. Just ignore the dying part of the process.

Do have to admit it took a few tries to get the process right, but I can print one in a flash now. Getting the right paper is important, I tried loads of types before finding one I was happy with, also applying enough heat and pressure in order to transfer the toner can be real hard to judge - as long as you don't over-heat the copper clad (It will tarnish initially, then it will start to unclad itself!) you can always just scrub off the toner and try the transfer again.

Paper wise, I use - Staples Photo Colour Laser, Glossy Paper A4, 180gsm

common gotchas -

Spending loads of money on special "Transfer paper" that doesn't seem to perform any better than a good colour laser gloss paper.

Photo "paper" made from plastic that will just melt while ironing.

Not ironing the edges of the design enough (The edges of the design are the hardest to transfer)

Not soaking the paper off for long enough (Soak it, scrub it lightly to permeate the back of the paper, soak it again.....then peel it)

:)

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    \$\begingroup\$ One way to avoid problems at the edges is to use a slightly oversized board, worth the money of the extra board. \$\endgroup\$ – russ_hensel Jul 7 '10 at 19:03
  • \$\begingroup\$ That's true...cheers Russ \$\endgroup\$ – Jim Jul 10 '10 at 14:45
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Get Pulsar's PCB-in-a-box kit: http://www.pulsarprofx.com/PCBfx/main_site/pages/index.html With a decent laser printer, you'll be in good shape. It's not perfect, but if you follow his suggestions, you'll be well on your way.

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  • \$\begingroup\$ and in a flash of facepalm, I'll add that when the instructions refer to the lighter blue side, it means the side that's almost white. I thought it had a white side and a blue side and couldn't for the life of me get the toner onto the copper. Turns out the shiny side (white) is the side coated with Dextrin. \$\endgroup\$ – Flyguy Aug 18 '10 at 2:50
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I had the same struggles you did a couple months ago when I first started doing this and for my process two things mattered the most:

  1. I never got photo paper to work. I tried a couple. I use magazine paper. Any magazine printed on nice glossy paper works. The main thing is that it needs to be thick enough not to jam in the printer.

  2. I use a laminator. I tried the oven technique as well as the iron and neither gave me good results. The GBC laminators sold on ebay are popular in the yahoo homebrew PCB group. I also saw one cheap at the local costco.

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I use the HP Professional Laser Paper 120 soft gloss ($20-30 for 200 sheets) with a Samsung laser printer and it works great. I iron the board for a couple of minutes and then I soak it in water and remove the paper with my fingers.

EDIT: I forgot to mention that there's no toner left on the paper with this particular kind of sheets (which is the first I've tried for this job, I must have been lucky). The only problem is that, sometimes, if I press too much when ironing, some traces can come out a bit thicker.

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I've never had any real sucess with toner transfer. I tried various kinds of paper including magazine paper ands several types of glossy paper and never managed to produce a usable board. They all either had missing traces, or were slightly smeared in places leading to an unusable board.

The special press and peel paper worked a lot better but even that it generally took me several attempts to make a usable board.

So I bought a cheap UV lightbox and used the photoresist method which just seems to work every time with no fuss.

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One problem I encountered recently is the varying melting temperature of toner in different brands of laser printers. After some reading, it turns out that recent Brother printers have a much higher melting point (around 400C I think) than other printers.

The printer I started out on was a HP LaserJet 1020 and I had problems with getting the toner too hot using an iron, causing the 'smudging' that another post mentions. The solution for me which gave excellent results was to use a hot roll laminator (put the board through 5-10 times) - supposedly the combination of temperature and pressure is the key. Using an iron on a cooler setting should also work.

However recently I've switched to using a Brother HL-2142 printer and the laminator was no longer working. Temperature is the problem, so going back to the trusty iron and cranking up the temperature seems to be effective. The blue transfer paper doesn't much like the heat and starts to wrinkle and warp, so I'm going to try the glossy magazine pages that others have mentioned.

Other tips:

  • rub the board until shiny with a plastic scouring pad - the rough surface is supposed to help the toner to adhere. Don't use steel wool as you'll end up contaminating the copper
  • wipe with isopropyl alcohol - avoid finger prints on the board past this point
  • for the laminator method - affix the paper to the board using a piece of tape at one end only - always feed the board through the laminator tape side first
  • for the iron method, I find that one or two sheets of paper on top of the transfer paper helps (and stops the plastic melting and sticking to the iron in the case of blue transfer paper)
  • cupric chloride is the best etchant as it can be reused again and again after simply bubbling air through the solution - it also etches well at room temperature
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You could build (or buy) a PCB milling machine. The Mantis 9.1 mill can be constructed by a hobbyist, and depending on what parts and supplies you have lying around, can be built for somewhere < $200.00 USD. Using a mill has some advantages over the other "home brew" methods... no messy etching agent to deal with, no goofing around trying to transfer laser toner to a PCB, etc.

See: http://makeyourbot.org/mantis9-1 for more details on the Mantis project. Also, here: http://therearenonames.wordpress.com/2011/11/27/ooo-baby/ is a blog post with some video of one in action, that was made by a guy here at Splatspace. He shares some thoughts on the merits of, and issues with, these mills.

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grab old XY plotter, break it apart and attach Dremel flex shaft engraver instead of knife/pen.

this type of setup makes PCBs like magic. *using home made cnc mill for pcb prototyping myself

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  • \$\begingroup\$ How do you get from a PCB layout package to the plotter? Does the cnc read Gerbers? \$\endgroup\$ – Paul Uszak May 4 '17 at 20:35
  • \$\begingroup\$ if I'm not mistaken, GerbView can export svg files. \$\endgroup\$ – Alex D May 4 '17 at 22:27
  • \$\begingroup\$ I'm on *nix and using gerber-to-svg (available via npm). Another tool you might want to try is gerbv.geda-project.org (never tried it but description looks promising). and yes, answering your first question: I'm using Universal G-code sender from laptop to cnc. available on github. just dont forget to mirror your vector before sending to cnc \$\endgroup\$ – Alex D May 4 '17 at 22:29
  • \$\begingroup\$ This method is slow, limited in capability(small bits == really slow), and really all around bad. CNC is good for a lot of things, prototyping PCBs isn't really one of them. \$\endgroup\$ – Matt Young May 4 '17 at 23:04
  • \$\begingroup\$ slow-ish, yes, limited - yes. but works perfect if you need 1 or 2 layered PCB made at home fast. even slow milling will be faster vs ordering prototype samples from a third party company though \$\endgroup\$ – Alex D May 5 '17 at 8:22

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