Folks,

I have about 30 assemblies on hand that slightly exceed our internal
specifications for overall bow and/or twist percentage.  I've been asked
to identify a process to get these back into production.

In the past, I've conducted experiments where we took scrapped units
(with a much higher degree of twist) and screwed them down into their
frames, and then baked them at 125 degrees C for 24 hours.  This process
removed almost all the warp.

I'm looking for an easier way, if one exists.  

If I place these units upside down in a heat proof rack and subject them
to a similar heat cycle, can I expect the material to relax enough to
accomplish my goal?  I think this might get rid of most of my bow, but
I'm not sure how much effect it will have on twist.

My product is a double sided four layer board with overall approximate
dimensions of 190 X 120 millimeters.

Any suggestions would be greatly appreciated.

Thanks in advance,

Leland

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