Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

Thank you for sharing your 2 cents, Harvey.

I tried cold toner transfer on glossy coupon flyers from McDonalds,
but they failed to lift from the paper.   Looking around for paper that was "glossy but flexible" to print on, I also found and tried a  Techni-tool catalog cover, a CVS Pharmacy sticker backing, and an Avery address label sticker backing.    All failed.   So I'm postponing my cold toner transfer tries until I can get some Office One "Business Gloss" 32lb. 92 brilliance glossy paper Roland F. Harriston reported worked well awhile back.

Meanwhile, a bunch of my circuit's artwork piled up on a pile of ORACALl 651 vinyl stickers.   So I got out the iron & did some that way.

My first impression looked good.   So I etched it with ferric chloride and tinned the traces with Tinnit solution.    It looked great.   Until I looked a little closer and notice I'd forgotten to print the pads on this through-hole board.   D'oH!!!!   But it had another major flaw -- an unwanted trace shorting out 3 pins on an opamp chip.

So I re-ironed the board by following Adam Kohring's instructions to the letter:
Print Your Own Circuit Boards
EXCEPT I ironed it on for 5 minutes, rather than 2.

It worked.   The traces are well-defined.   However, about 30% of their
interior is lacking toner where it ought be.   Does this mean I need to
buy a new toner cartridge to replace the original  one I've been using for
11 years ?

Well, on October 3, I removed the old image and ironed another one on, following Adam Kohring, since I had two more artwork prints.   This time I used a timer to ensure I only ironed it 2 min.

It failed.    Maybe I didn't hold the iron still enough for 20 s.
Maybe do it for 30 s.    However, I DID NOT get the voids in the traces
that I did last time.   That's good.

My third try WORKED!   YAY!   The traces are about 95% covered on
their interiors.   I just gotta remember:
2 min. in oven -- 30s holding down the iron--2 min. total ironing.

I will go over the tiny holes w/ Sharpies.

I couldn't really do the holes using the 3X magnifying lens.  They
were too hard to see until I put them under the 10X loupe.

Oct 14

I just went over the tiny holes in traces using an ultra-fine tipped
Sharpie.   My Vision Technologies VT100 19in. CRT magnifier is inval-
uable for this purpose.   I saw holes in the toner as big as
0.005185 of a 0.086 in. trace, or 0.0004 in.  That's about 0.4 mil.
I filled 'em in with my ultra-fine-tip Sharpie.

WIlll etch it tomorrow,
Alan