I do this all the time.  Most of the time I put down a box outline along the edge with the layer number in it if I have enough room.

The only time I've ever had a fabricator querying it is if there's no room for the layer number and I've used a solid box instead, though this has only been on a couple of occasions.  It can be quite helpful for "reassurance checking" where you have more than four layers and darker solder masks.

As a designer I've never had a board with missing layers, but in my first job as a CAM Engineer it happened a handful of times before checking to netlists came along.  These days a check against the ODB++ or IPC-356 netlist should show missing layers before the fabricator ships the boards.


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]


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