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Date: | 10 Oct 96 13:03 CDT |
Content-Type: | text/plain |
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We are building a board that has 8 layers with multiple ground planes, this
combined with Entek plus coating and a no clean process is making it
difficult to optimize the wave solder profile to get 100% fill with a
fillet on all pins on the top side of the board.
The IPC A-610 rev B specification calls out 75% fill as being acceptable
(table 4-1, pg. 52) on through hole solder joints. We are pushing our
subcontractors to get 100% fill with a fillet on each pin.
Since we are setting our expectations to 100% fill on these solder joints
the subcontractor is having to touch up some of the solder joints to meet
this requirement (they are touching up the pin from the solder side letting
the solder flow through the board to the top) Thus my question...
Is a solder joint that is 75% filled over the wave stronger (more reliable)
than a solder joint that has been touched up to get to 100% with a fillet?
What is the effect to long term reliability of touching up a through hole
solder joint?
I would really like some reference material on this subject if anyone has a
source.
Thanks,
Mark Weiler
[log in to unmask]
512-728-8323
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