[sdiy] PCB making: how to get a transparent foil with real black lines?

[Neil Johnson]

Martin,

> Is there someone out there how can propose a better method to get a
> layout on film?

Laser printing onto translucent tracing paper produces excellent results:

*) the paper has a nice rough surface to bind the toner to, and

*) it is opaque to UV, so can be used to create UV masks.

You *might* have to increase the exposure time a little to account for the
attenuation, but a little experimentation will soon sort that out.

There are plenty of pages on the web about using tracing paper, suggesting
anywhere from thin 75gsm (crinkles in the printer, so have to flatten it
first, but short exposure time) to thicker 120gsm paper (doesn't crinkle
but longer exposure time).

Cheers,
Neil

--
Neil Johnson :: Computer Laboratory :: University of Cambridge ::
http://www.njohnson.co.uk          http://www.cl.cam.ac.uk/~nej22
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