Playing catch-up example:

31032/1B amendment 4 defines "edge spacing" as "as-specified".  In other words: hey designer, start thinking about those edges and accept up to 50% reduction.
If the designer doesn't specify, then it defaults to A-600 Class 3 (hope we double checked the 6012 tracking :))

31032/1C (draft) does away with the A-600 Class 3 default and puts a 2.5mm max on the edge defects!

I'm not saying this is the correct answer, but DSCC is WAY out in front of us w.r.t. responsibility, authority and transition plans.

Chris





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31032/1C (draft)

3.5 External visual and dimensional requirements......The figures, illustrations, and photographs contained in IPC-A-600 can aid in the visualization of externally observable accept/reject conditions of printed boards or test specimens.

3.5.1 Base material.
3.5.1.1 Edges of base material. Burrs, chips, delaminations, haloing, nicks, and other penetrations along the base material edges of completed printed boards shall be acceptable provided the defect does not reduce the edge spacing specified by more than 50 percent. If no edge spacing requirement is specified, any base material edge defect shall not exceed 2.5 mm (.0984 inch). Base material edges include the external edge of the printed board, the edges of cutouts, and the edges of non-plated-through holes. Loose metallic burrs shall not be acceptable.


31032/1B a4 ----------------------------------------------------------------------------------
3.5 External visual and dimensional requirements. Printed board test specimens (the finished printed boards or supporting test coupons, as applicable) shall conform to the requirements specified in 3.5.1 through 3.5.5.5 as applicable. Scratches, dents, and tool marks shall not bridge or expose signal conductors, expose base metal, expose or disrupt reinforcement fibers, reduce dielectric properties, and reduce spacing below the minimum requirements herein. IPC-A-600 contains figures, illustrations, and photographs that can aid in the visualization of externally observable accept/reject conditions of test specimens. If a condition is not addressed herein, or specified in the printed board procurement documentation, it shall comply with the class 3 criteria of IPC-A-600.
3.5.1 Base material.
3.5.1.1 Edges of base material. Burrs, chips, delaminations, haloing, nicks, and other penetrations along the base material edges of completed printed boards shall be acceptable provided the defect does not reduce the edge spacing specified by more than 50 percent.
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