Homebrew PCBs

Bingo! NaOH worked like a charm but took a little longer than 10 
minutes.

Thanks to all for your suggestions.

Morris


--- In Homebrew_PCBs@yahoogroups.com, Adam Seychell <a_seychell@...> 
wrote:
>
> How can I get this stuff off? 
> > I have tried acetone, alcohol, soap & water, citrus cleaner and 
> > Shellite (a hydrocarbon based solvent) all to no or little avail.
> > 
> 
> Its most likely negative dry film resist. If so then room temp 3~5% 
NaOH 
> will strip it off in a 5~10 minutes (no scrubbing as it will swell 
and 
> just lift off the copper). You'll damage the copper removing it any 
> other way. Most common solvents and household cleaners won't touch 
these 
> photoresists once polymerised.
>