--- In
Homebrew_PCBs@yahoogroups.com, David Mitchell <gossiphog@...> wrote:
>
> I have a number of cricuts that I got broken from ebay for $20 or so,
> shipped, and repaired myself. Some are much easier to fix than others, but
> if you're handy as I suspect most on this list are, pretty much all are
> repairable.
>
> I like the vinyl etch method, but had problems with it floating off when I
> was using the "metal salt" etch on aluminum.
The few I made with vinyl, I didn't have any problems with ferric chloride.
> Not to get too far off the topic of PCBs, I got around the edge leakage
> issue by cutting a positive mask from vinyl (vinyl goes where you want the
> metal removed), transfer to the metal, and spray-paint over it. Then peel
> off the vinyl. The spray paint works as a much more effective etch resist.
>
Look in Links, Files, and Photos for Scratch-n-Etch. Dykem metal marking fluid works much better than paint, in that it scratches off more easily and cleanly. And works quite well as a resist. Just modify a pen for your plotter with a carbide or diamond tipped metal marking pen tip, and maybe add some lead shot to increase the pressure. No offset compensation needed.
Steve Greenfield AE7HD