Electronics Forum | Thu Oct 28 09:52:39 EDT 2010 | dyoungquist
Try rotating your board 90 degrees when running it through your oven. Will probably solve the tombstoning issue on that cap but might cause tombstoning elsewhere.
Electronics Forum | Fri Oct 29 07:10:40 EDT 2010 | scottp
I agree with DucHoang. If your board and reflow profile have not changed then I would suspect incoming parts. We've seen tombstones when a chip supplier had plating problems.
Electronics Forum | Sun Oct 31 11:07:09 EDT 2010 | Mark
http://www.shanelo.co.za/Article%20to%20assist%20with%20Stencil%20Design%20Guidelines.htm Stencil design
Electronics Forum | Tue Nov 30 07:53:16 EST 2010 | edmaya33
could be a printer or stencil issue. try to check your printing repeatability. Suggest to use SPI for a checking paste volume/height/area.A regular stencil cleaning may reduced your headache.
Electronics Forum | Thu Oct 28 10:06:12 EDT 2010 | d0min0
We saw this idea in older posts, but - we don't want tombstone elsewhere :) - rotating the boards before oven is complicated, so it could give more problems than the tombstoneing :) the issue is not 100%, it is 10 to 50 boards with component up per 3
Electronics Forum | Thu Oct 28 16:11:43 EDT 2010 | dwonch
Dealing with these intermittent issues can be frustrating! Can you narrow down if the defects occur during a specific time in the run? i.e. beginning or end? Or, maybe after a pause in printing such as stopping the line for lunch? Are there a lot of
Electronics Forum | Thu Oct 28 08:28:33 EDT 2010 | d0min0
Hi, previous topics found closed so I couldn't continue on them, but wanted to ask maybe something that we don't already know paste shape and placement ok, reflow 12 zones profile looks ok (same since 2 yrs), component placement ok, one reference i
Electronics Forum | Thu Nov 04 04:27:46 EDT 2010 | d0min0
thanks for all the feedback... we also checked, just in case : - bake the components (no visible improvement) - bake the pcb (50% less tombstone components) - finally we changed LF paste to completely different manufacturer - and booom 0 (zero) tombs
Electronics Forum | Fri Mar 06 16:17:38 EST 2009 | aj
whats your board finish?
Electronics Forum | Thu Mar 05 11:53:09 EST 2009 | dcell_1t
Hello to all. for certain time, we have been struggling with some issues on a PCB where have tombstoning on 0402 components (due to pad design) and dewetting in qfp256 0.5 mil pitch (discussed on another threads on this forum) component, we have pro
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