Part of the CAM process is deleting any board outlines that appear on copper layers, solder masks, and silkscreens so if you don't include it you've saved the CAM Engineer some time.  They do require the board outline some how though and depending upon the quality of the information you're providing to your fabricator, they need a dimension from a feature such as a hole and pad to the edge of the board, plus the x/y dimension of the board.

I include the outline as a separate gerber file/odb++ layer plus the outline on a fully dimensioned fabrication drawing.

In my days as a CAM Engineer if we didn't have a dimensioned drawing then we'd use an outline if the customer had provided one in the gerber and tick the box on the CAM record saying "rout to corner blocks".  This was for a "low-value" customer though, i.e. small scale operation, low board cost.  Obviously if it was a major company such as Nortel/Marconi/BAE then the job would go on hold until we'd had instructions from the customer.

Generally we'd not use any customer supplied rout files but create our own from the customer's drawing.  I expect that a more up to date CAM program would be able to automatically create a rout program from a closed polygon which is why they're asking for one.

Regards,

James

James Head BEng CID+ MIIE MIET
Senior PCB CAD Engineer
Crowcon Detection Instruments Limited
2 Blacklands Way
Abingdon Business Park
ABINGDON
OX14 1DY
Telephone: 01235 557700 extension 289
Fax: 07092024504
E-mail: [log in to unmask]


-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Barbara Burcham
Sent: 31 July 2012 15:55
To: [log in to unmask]
Subject: [TN] Board Outline on gerber files...Yes/No

I have run up against the question of putting the board outline on each gerber file. One fabricator who needs it on at least on file.
What do fabricators need regarding this?
What about board outline on the stencil gerbers for the Stencil Makers?

Regards,
Barbara Burcham, CID
Sr. PCB Designer


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