Homebrew PCBs

Woods metal is an alloy of tin-lead-bismuth-cadmium. Hmm, low 
temperature solder. I suppose that is one way of tinning your boards :-)

Les

> Anyway, 'high' temperature alloys exist, like Woods metal.  It melts at
> around 50C, so that would work.  Only a couple of trivial problems remain,
> like is Woods metal attacked by etchant, and how does one pump molten metal
> onto a PCB?
>
> Hmm, PCB sits on a Peltier, cooled enough to avoid condensation.  Molten
> metal held in a syringe, forced out by plunger, retract plunger slightly to
> stop.  Same as solder paste.  If you test conductivity between the PCB & the
> shrine, you can see when the track start to get laid.  How to do wider
> tracks?
>
> PCB is etched, then placed in hot water to remove Woods metal.  Metal is
> reused.
>
> Right then, "who wants to try it", he says, thus showing an idea is worth
> zero unless you can show it works.
>
> Tony
>