Re: ATM board layout, what resist?

[Anthony Stillman <atmer@flash.net>]

>...recomended resist


Thomas,

I use to use photo-sensitive emulsion resists.  This is still the perfered
method when fine detail is needed. Pre-sensitized boards are still availble
or you can pour it your self.  Incidently, though more expensive, the pour
on stuff works better than spray shellac for protecting finished optical
surfaces that are attached to other surfaces which need to go back to grind.

For quite some time now I've been using laser printer carbon as the resist.
Regulary photo-copy transparency material works after a fashion, but its
not so great at transfering. After printing you iron the carbon off the
tranparency and on to the copper.  Do use paper towel between the iron and
the plastic.  Don't use the SO's good iron.  (my iron came from the thrift
store)

In the back of almost any popular electronic hobbiest magazine you will
find an add for material specifically designed to transfer after its been
printed to/photocopied to (links? anyone?).  Even with this you will need
to touch up with a Sharpie, wax, nail polish,...  With all the effort, for
one off work I often resort to press apply copper and point to point
soldered wire warp wire.

Let me add that I've taken to using the commertial transfer material for
jewlery and have managed extrodinarily deep etches before pin holes become
a problem.  Carbon is a great resist.

Anthony