On Fri, 11 Jan 2002, Tony Firshman wrote:
> I know Stuart Honeyball produced some commercial boards but printing
> direct onto special film.
>
> How? He didn't have a laser printer at the time and I did them for him
> (8-)#
>
> It apparently worked very well, but there is loss of quality. No chance
> of .5mm romdisq type pitches by this method.
The loss of quality is because you need to reverse the image in the X and
Y planes.
(fixed pitch font required here)
__________<Print
___________/__________\____________ When printed on top, the UV light
. . can go under the printed track to
. . expose PCB where you want the track
. . to remain. ('.'s = UV light)
______________.____._______________
___________________________________ When printing reversed, the printed
side contacts the etc resist
directly and there's no UV light
getting under it.
___________________________________
\_________/
^Print
This way, I usually avoid problemms with .007 or .008 tracks, especially
at corners.
(I write product manuals for ordinary people :o)
Dave
