Homebrew PCBs

Andrew wrote:
>
> > SurfThenet wrote:
> >
> > Has anyone ever tried to make a printed circuit
> > board by printing a reverse image onto a sheet
> > of aluminium foil [with an ink jet printer],
> > then plating copper onto the exposed trace?
> > This sheet would be epoxied [copper side down]
> > onto a thin fiber glass board, allowed to set
> > and then caustic soda would eat the aluminium
> > away leaving the copper trace behind.
> >
> > Sound feasible? See any obvious problems with
> > the approach?
>
> Apart from the fact that is sounds harder and
> more expensive than just using photographic
> emulsion as nature/god/kodak intended.
>





















You don't have to use silver you can use potassium or ammonium 
bichromate. It is nasty stuff but you can spin coat the aluminum foil 
with  a fresh made gelatin, albumen, agar, etc and  bichromate mixture 
and not be very expensive. The hologram guys have a lot on bichromate.

Gordon
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