[sci.electronics] PCB - Gerber formats etc

nivek@rover.ri.cmu.edu (Kevin Dowling) (10/02/89)

>From: phil@ingr.com (Phil Johnson)
>Subject: Re: PC Boards: Gerber formats

Phil,
Thanks for your posts. 

	 I have found a couple of PC houses that are shifting away from
	 Gerber.  Several are doing the artwork directly on
	 photo-typesetters like the linotype. I found a company that
	 can take our McCad disks from the Mac and they directly print
	 on a Linotype. No Gerber.  I tried on one of the Linotypes
	 here on campus and got great results with using a mylar film.
	 (Kodak HN LaserFilm #2692) At $11 for 11x17 pages the price is
	 right for the artwork. The drill 'tape' is directly generated
	 by the program too. The place we sent board designs to said
	 the were limited only by the board size capabilities of their
	 drilling machines (18x24 in their case)

	 I suspect many of the PC houses will find themselves having to
	 shift to this format. The typesetters are far more flexible
	 and faster than the old X-Y aperature technology. If the
	 program allows previewing on a laser printer there's no reason
	 why the same Postscript file can't be sent to a photoplotter.

	 You say people won't want to pay the cost for photoplotting
	 in Postscript but I think it'll be cheaper, easier and faster
	 in the long run. Boards of very high complexity can easily be
	 generated, without resorting to clever methods in 'painting'
	 areas.

	 I guess if these programs very easily provided the Gerber
	 output simply as a menu selection or something I wouldn't care
	 and I would get my boards and the gory details would be
	 transparent to me. Unfortunately, at least with McCad, it
	 isn't provided easily except through the use of translator
	 programs that assume knowledge of Gerber formats.

  Anyway, our boards should be back in a few days.

			nivek
Aka :	Kevin Dowling		Bell:	(412) 268-8830
Arpa:	nivek@rover.ri.cmu.edu	Mail:	Robotics Institute
				Carnegie Mellon University
				Pgh, PA 15213-3890