Homebrew PCBs

Mark Robinson wrote:
> I take the extra step of sandwiching a small strip of pcb material between the
> films using double sided tape. It gives a good edge for alignment and reduces
> the errors from the film bending around the edge of the pcb. Then I tack the
> film to the substrate using adhesive tape to stop anything moving while it's
> exposed, inverted and exposed again.

That sounds like it might be a good way to align toner-transfer transfers...

Take an L-shaped offcut of PCB material (of whatever thickness you're using) 
and transfer an alignment marker on one side.

Drill a hole in the centre of the alignment target, align it against the 
bottom transfer so the marks match up, then tape it down with double-sided tape.

Cut the area around the alignment mark out of the bottom transfer, then put 
the L-frame onto a lightbox.

Now take the top transfer, align it against the alignment marker, and stick it 
down.

Iron on as normal.


Does this sound plausible? Seems it might work a bit better than my 
tape-the-two-transfers-together method, which seems to fail dismally on 
anything PCB blank thicker than ~0.8mm.

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