Homebrew PCBs

On 14/04/2012 21:24, David wrote:
> Hi All,
> After looking at Craig's fasinating PCB spinning methods, an idea came
> to mind, seeing as the regular chemicals seem to be rare and expensive,
> has anyone tried silk screen printing emulsions? this in not the inks
> but the chemical used to make the pattern in a very fine mesh, the
> emulsion is spread over the mesh with a squeegy and after exposure to UV
> through the pattern[design] blocking transparency, the unexposed area is
> washed out with running water, the exposed area remains and is really
> pretty tough, is this resistant to etching chemicals? would this method
> work? has anyone tried?
> There would be no need to "develop" the PCB, just wash off with water!!
> I may be way off track with this but any comments and/or suggestions?


PCBs were made that way at English Electric Ltd, Kidsgrove, when I was a 
student there in 1962. The pattern was created on a silk screen, it was 
placed in contact with the copper, and the resist was applied with a a 
squeegee.

Leon
-- 
Leon Heller
G1HSM