Hi

If it's the spacing that is the problem, and not the
trace width, then we've had a problem come up on our
most recent board that may be related to your problem.

In our case, on a 5/5 board, which passed all the Mentor
standard checking (but not MDV) the PCB manufacturer said
that a lot of our clearances were under 0.005".

We tracked it down to being the Artwork Format - I had been
generating the files in 2.3 format (2 digits before the
decimal point, 3 after) which turned out to be too
coarse for this board. I regenerated the files at 2.4, and
most of the problems went away.

I don't know if this is any help, but it's something to
bear in mind.

Good Luck, and Regards

Brian Rusten

PCB Design Engineer
Aristocrat Leisure Industries
85-113 Dunning Avenue
Rosebery NSW 2018 Australia
Tel:    +61 2 9697 4699
Fax:    +61 2 9663 1412
E-mail: [log in to unmask]


> -----Original Message-----
> From: Lum Wee Mei [mailto:[log in to unmask]]
> Sent: Wednesday, 23 June 1999 14:35
> To: [log in to unmask]
> Subject: [DC] Inconsistent Gerber Output
>
>
> I have a question regarding Gerber output. Most of our
> designs are done
> with 6/6 (trace/spacing). One one occassion, our regular PCB vendor
> called us up and inform us that they found some 5/5 on a particular
> layout. However, when we call up the layout on our
> workstation with grid
> at 1mil setting, we found that the so-called problem area to be a
> perfect 6/6.
>
> Recently, this problem cropped up again with another new PCB vendor.
> Once again, our layout show a perfect 6/6.
>
> Can anyone throw me a light on what could be the problem. My Mentor
> Graphics rep mentioned that it could due to the CAM system used by our
> PCB vendor.
>
> Thanking in advance.
> Regards.
>
>