Homebrew PCBs

Alan,

as i said it is mainly colophony resin (the same flux used in many solder  
wires) and alcohol.
I know people who simply mix solid chunks of colophony resin with  
methylated spirits (ethanol alcohol) and apply it with a paintbrush. It  
works the same as my spray, but since a 400ml can costs only 8 eur here in  
Austria i simply buy the spray.

Colophony solves in alcohol, acetone, paint thinner, etc.. But i recommend  
methylated spirits (ethanol) since acetone gives a ugly dull finish.

In the past natural resins like colophony were widely used in lacquers for  
wood protection and stuff, but not any more.

The product i use is here:
<http://www.crcind.com/csp/web/ProdDisp.csp?lng=3&country=ALL&product=FLUX%20SK%2010&brand=KOC>

But as said you can just make your own if you can't get it. colophony  
resin should be readily available. Get as light a color as you can,
while you won't see it in the thin layer on the PCB it's still better.




While looking for the solder lacquer i found a very interesting thing:
<http://www.buerklin.com/gruppene/KapL/L177100.asp?l=e>

I've spend many, hours probably, thinking about using a metal brush that  
is heated in some way, but never actually got around to trying it. Seems  
it's time now. I reckon those are brass or steel bristles. Maybe even  
stranded wire or desolder braid will work. easy to build.

ST




On Tue, 10 Jan 2006 15:53:52 +0100, alan00463 <alan00463@...> wrote:

> I will look for "solder lacquer spray".   Nearly all the websites that
>
> mention are in the U.K.   Maybe it's called something different in the
>
> U.S.A.     I am wondering if this is the same stuff you would buy in a
>
> paint store in the U.S.A. for protecting wood?    Or is it something
>
> different?   I couldn't find it in Mouser, Digikey, or JameCo
>
> catalogs, even looking under the generic heading "chemicals".
>
>
> The closest I found was "silicone  conformal coating" and "urethane
>
> conformal coating".   These are anti-fungal, anti-moisture coatings
>
> for protecting the circuitry from harsh environments.   Probably not
>
> what you had in mind.
>
>
> Stefan, the "solder lacquer spray" you use is transparent, is it not?
>
> Does acetone dissolve it once it has hardened?   Can you see where it
>
> has been removed vs. where it remains on the copper?