Michel Baguet <
bagmik@...> writes:
> Well, line up is not a problem. it's the transparent getting
> deformed when heated.
Ah, that. What I did was calibrate the deformity once (transfer a 3x3
square to a board and measure it) and compensate for it in PCB. To
align two sides, I ended up using targets centered on the sides of the
board, rather than diagonally opposite. Also, I've tried using a hand
iron to tack down the paper before laminating it.
Photomask is easier because there's no heat, you can see through the
paper to line it up, and nothing moves during the exposure.