PCBs

[jc]

>What do people think about "iron-on" PCB resists?
>The description I saw in Mouser said that there was no chemicals involved. How
>then do you etch away the copper?

I think it's useful in really tight designs though your don't really need
it if you've got a printer or a photocopier and a good source - you can
print your traces to scale on paper and pierce small holes where the parts
solder on, tape it to the copper board side and start inking through the
holes for guides and then trace the connections by hand after removing your
guide sheet ...

when I use the iron-on stuff I always expect a retouch anyway ... if you're
not too fussy about doing touch-ups and you've got a laser printer then
it's rockin' ... after a few really botched runs I found the trick is to
heat the paper *really* well while applying a bit of vertical weight for a
good five seconds (this provided the iron fits over the hole board evenly)
... I've never had one turn out perfect all over, but there's always at
least a basic shadow to work from in the poor areas ... good luck

jc