a good idea if you are going to do production and make many, many
boards.  i suspect litho film is pretty tough.  you can also laser print
the layout (on proper transparency stock) and use that as a mask, though
solid dark areas like ground planes can be a problem.  now that you've
mentioned the litho thing, i suppose you could also take a plot and use
it as a mask to make your own litho mask, though from the litho film i'm
vaguely familiar with you may need a lot of uv or time to expose it.=20
mostly the neat thing about using a plotter is you can do it in house
without any delay and solid areas like ground planes come out well.=20
before going the plotter route last time i made boards i tried laser
printing and always had to try to fill in the gray areas that were
supposed to be solid.  it's also fairly cheap, the pens are the main
expense but if you take care of them and don't use the very fine ones
they last a long time.  of course you have to have a plotter or access
to one.

i've also used plotter prints for panel layout and labeling, again
printed backwards so that the ink is towards the box and used super 77
to attach it (though i suspect there are better spray adhesives, i now
know 3m makes some stronger ones).  as i said, this also had the layout
for drilling the panel and worked out very nicely.  the ink is protected
because it's on the inside, and it looks great with the ink on the rough
side of the mylar and the smooth side out.  for this project we just did
it in black and white, but of course you could use color.  i plan to use
the same method on my future projects.  if the panel is already drilled
etc. the holes make a great alignment guide, and the mylar can be cut
easily with an exacto knife where things are to come through it.  it's
also easy to clean the panel which can be a real help.

Falcon Wireless Tech Support - KF4HAZ wrote:
>=20
> For a the lowest cost software (free) I use MSpaint.
> I make my drawings "E-up Positive" (as viewed from top of pcb)
> To make the resolution easier to get fine detail I work at 5x scale.
> This works out to 480 dpi, then I scale it back to by loading it into
> either,
> MSphoto or Kodak imaging and setting it to 480 dpi (paint uses 96dpi),
> I then save it as a tiff @ 480dpi and ftp it to LithoPlate&Negative
> 67.32.155.204
> They Print a Litho on photographic film,
>  a true litho will block sunlight in the black areas.
> They charge ~$30 for a 12"x18" board (which may contain several pcb lay=
outs)
>=20
--------

--=20
Philip Stortz--"In Germany they came first for the Communists, and I
didn't speak up because I wasn't a Communist.=20
Then they came for the Jews, and I didn't speak up because I wasn't a
Jew.=20
Then they came for the trade unionists, and I didn't speak up because I
wasn't a trade unionist.=20
Then they came for the Catholics, and I didn't speak up because I was a
Protestant.=20
Then they came for me, and by that time no one was left to speak up."
-- Martin Niem=F6ller, 1892-1984 (German Lutheran Pastor), on the Nazi
Holocaust, Congressional Record 14th October 1968 p31636.

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