photocopier acid resist etching (printed circuit boards)

was thinking about you guys.
wanted to make a "dog tag" but wanted it to be "pretty" (not just steel
letter stamps but allowing me to select a aesthetically pleasing font).
remembered i'd seen something on the internet a while ago about this and
found a website.... (can't remember, maybe i even heard about it here?)
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slightly modified his technique and made this (the "sandy peak" tag, not the
other one)
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it didn't turn out "perfect", i think i gave it a little deeper etch than
the toner could resist.
seems to me this technique could have other fun/interesting applications.
(i had no idea xerox toner could resist acid well enough to do a
"photoresist" etching. cool.
b.w.
(but i bet many of you guys already knew this, was new to me.)
(it's a lot more work than just using steel letter stamps... but if you
want it to be "pretty", this was cool.)
Reply to
William Wixon
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Another good site for this is
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-- Regards, Carl Ijames carl.ijames at verizon.net
Reply to
Carl Ijames
I've made brass nameplates using this method, but used photosensitive spray and a mask for the resist part. The back side and edges were coated with some asphaltic varnish I managed to pick up at Orchard Supply. I used the PC to generate the original mask, laser-printed onto a piece of plastic overhead material. I already had a UV lamp for exposing the resist. Here's the deal with deep etching. You have to keep pulling the piece out and look for undercutting. If you start getting undercutting or have thin spots in the resist, the piece needs to be dried off and the spots need to be hit with a resist pen. I've found a Sharpie works just about as well as the off-the-peg product. Ammonium persulphate instead of ferric chloride seems to give a smoother etch, too. Much easier to see what's going on since the reaction products are clear. Takes longer, though.
Stan
Reply to
stans4
One really important thing when etching deep is bubbling. Get a weak air pump (like used in aquariums) and have a tube in the bottom of your etching tank. Drill some little (1mm) holes into the tube (you closed the end of the tube, right?). The bubbling moves the etchant and removes the slurry from the part to be etched. _Way_ better results!
Have been playing around with that to get these parts:
The small letters are 4points high. It was etched, blackened (NaOH) and then ground. I made several, only one qualified. :-)
On the base, lower left, is also etched brass. The etching is 1/2mm deep and has very precise corners, but the bottom of the etched area got a bit corny.
I made both with films and a foto-positive etch resistant spray. The film was printed on a laser printer, but next time, I'll let make them at a print shop. Much better and only little money.
Nick
Reply to
Nick Müller
More information (and current massively extensive discussion on modifying Epson printers to print directly onto metal)
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I've already posted my method to that group, but, long story short, HP Glossy Laser Photo Paper (/not/ inkjet paper) + Xerox DocuColor 12 photocopier (I've never seen a Staples that does not have one of these) + laminator (GBC Creative 9" also from Staples) seems to be the best combination. I used to use an iron but the laminator works SO much better. Many people report using inkjet paper 'works better' for transfer, but you can seriously screw up your printer/copier using this.
Also search for using cupric chloride rather than ferric for etching.
Brass and copper are easier. I've been looking into etching stainless but the chemicals involved aren't as easy to obtain. Learning to do this kind of etching requires a LOT of experimentation even if you buy a serious setup (developer chemicals, darkroom, lightbox, etc), but 'home based' setups can produce stunning results.
To prevent undercutting for things like tags I tend to use brass half as thin as what I want, and cut two of the exact same 'tag', or the 'tag' and a solid 'back', then glue together with JB Weld rather than trying to cut through seriously deep metal. Anything thicker than .010" can be tricky or take a few millenium to cut through.
Reply to
Fenrir Enterprises
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I haven't tried ammonium persulphate, and recently have been using ferric chloride, but in the past have etched a number of boards ok with hardware-store HCl and drugstore H2O2, in equal parts. Also, I use blue Press-n-Peel, as noted at
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. -jiw
Reply to
James Waldby

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