I have used the rosin laquer many times with good results.
It just takes slightly longer than regular paint to dry.
You can either mix your own colophony resin in denatured alcohol to paint
it on, or buy a spray can:
<
http://www.banzaimusic.com/Solder-Lacquer-SK10-400ml.html>
I'm not usually one for spray cans, but this was very cheap for a big can
and will last forever.
I've also used it as a flux on old breadboard that was hard to solder with
good results.
You can use it as a general purpose flux to drip on stuff or dip wires in.
ST
On Wed, Aug 21, 2013 at 7:55 PM, Charles R Patton <
charles.r.patton@... > wrote:
> Dave,
> I agree with your conclusion. Spray coating the copper just after the
> resist has been removed is a good look and what I did with acrylic spray
> at times in the past. The epoxy we used made rework almost impossible.
> I haven't done much in the area of things that need re-work once built,
> but generally I understand that acrylic or urethane spray coats are also
> good and allow reasonable reworking. I do know that there was (still
> is?) a patented PCB production process where after the resist was
> removed, silk screening added, the board was coated with a "protective"
> coating. The coating was thin, and basically a flux, but it also acted
> as an oxygen barrier so the copper remained solderable for some period
> of time. Personally I always felt this could be duplicated by using an
> alcohol/rosin solution. (A cheap source of rosin is dance supplies.
> Dancers put rosin on their ballet shoes.) Paint/dip your newly cleaned
> board with the solution and you will have pre-fluxed it and protected
> the copper surfaces from oxidation. Rosin by itself is dry and
> non-sticky (be sure the alcohol is pure and not drug-store rubbing
> alcohol which often has some mineral oil as a percentage of the
> solution). A disclaimer here -- I've never done this myself as my
> personal PCB needs have changed drastically from the days described
> above. I make a one off prototype using toner transfer that I
> immediately assemble by hand or I send off the files and have a board
> house make a bunch.
> Regards,
> Charles R. Patton
>
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