Re: gEDA-user: Outputting negative plane layers from pcb?

[Karel Kulhavy <clock@twibright.com>]

On Tue, Oct 19, 2004 at 01:21:43PM -0400, Randall Nortman wrote:
> The PCB fab house I intend to use requires that all ground and power
> planes be printed in negative in the Gerber files.  (See

They basically say "Please make sure your plane layer data are in negative
format". There isn't anything like "negative format" and they don't provide
a pointer to "negative format specification". The paragraph doesn't seem to
make sense for me.

If they state they support Gerber RS274-X, send them Gerber RS274-X. If they
make it wrong, then slap them with the spec:
http://nexp.cs.pdx.edu/twiki-gerber/pub/Gerber/GerberFiles/rs274xrevd_e.pdf

Some PCB manufacturers say they support Gerber RS274-X and actually don't. I've
hit one. I just moved on after learning that :)

Cl<

> http://www.pcbfabexpress.com/faq.jsp#q10.)  They say that most CAD
> software does this by default, but I don't see any mention of it in
> the manual.  I can see that I can select "invert" when printing the
> Gerber files, but I don't see any way to specify particular layers to
> be inverted but not others.  I suppose I could print twice, once
> inverted and once normal, and then just ship them the right file for
> each layer, but this seems like a pain.  Is there an easier way?
> 
> Thanks in advance,
> 
> Randall Nortman