Larry;

Running the soldermask onto a land near a via hole is fine. But running a
soldermask to a board edge is another issue. When boards have routed edges,
the soldermask tends to chip and flake the soldermask. It is recommended
that the mask stay away from the cut edge, in order to eliminate this
chipping tendency.


At 12:00 PM 6/19/96 -0700, Pucket, Larry Lee       9784 M wrote:
>What are the problems with running the soldermask to the edge of the printed 
>wiring board and non-plated holes?  We have been keeping it away by 50 mils 
>but you see alot of commercial boards with it to the edge.
>
>Does it depend on board material?  Does it depend on whether it is 
>commercial versus military?  Does it depend on dry versus liquid soldermask?
>
>Any ideas would be appreciated.
>
>Larry L. Pucket
>Dept. 9784 MS0624
>Sandia National Laboratories
>P.O. Box 5800
>Albuquerque, NM 87185-0624
>
>Phone: (505)844-1711
>  Fax: (505)844-7428
>
>Email: [log in to unmask]
>
>
Regards,

Gary Ferrari
Tech Circuits
(203)269-3311
[log in to unmask]