Electronics Forum | Thu Aug 03 11:39:19 EDT 2006 | slthomas
Is your squeegee cleaning process adequate to guarantee no transfer of paste residue between jobs? Personally I wouldn't risk it, but then again it's easy for me to say since we don't do lead free.
Electronics Forum | Tue Oct 31 16:30:32 EST 2006 | John S.
SnPb No-Clean. We've done it on bare boards with alcohol and an ultrasonic bath, but that seems very agressive on a half populated board. Thanks John S.
Electronics Forum | Tue Oct 31 22:16:53 EST 2006 | davef
John S.: IPA is dangerous choice. Look here: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=43133
Electronics Forum | Mon Nov 06 10:07:29 EST 2006 | slthomas
Will they give you the opportunity to develop a DOE to look at quality vs. print life? It probably depends on the kind of placement equipment you have, but with our chipshooters we always had missing/misplaced parts if we populated dried out boards.
Electronics Forum | Wed Feb 07 07:50:34 EST 2007 | davef
Jax: Matt works for Sipad. In the past, he has posted questions, often with pix, seeking help resolving production issues, often involving issues with bare boards. He's not pimping his product.
Electronics Forum | Mon Feb 19 12:23:46 EST 2007 | Hussman
I have about 40 jobs that don't have fids, yet I have to screen print adhesive or paste. I have to use the pads on the board for auto alignment. But then again, I don't use DEKs so I am inferior?
Electronics Forum | Wed Aug 22 09:59:06 EDT 2007 | slthomas
Are there long lags between print and place, and place and reflow? Could your paste be losing some of it's tack?
Electronics Forum | Mon Feb 18 11:31:02 EST 2008 | davef
Print paste through the new stencil with a piece of mylar [or other clear plastic sheet about the thickness of paper] between the board and the stencil. Dispose of the mylar according to local practice after confirming proper aperturation of the sten
Electronics Forum | Thu May 08 21:19:46 EDT 2008 | davef
Don't allow x-outs. There has been previous discussions here in SMTnet that maybe found by searching the Archives. Steve Gregory calculated that printing paste on X-outs cost him about $50k a year.
Electronics Forum | Mon Aug 18 15:18:08 EDT 2008 | realchunks
Open the same size as the via's anular ring. Any slight off print will wet its way back into the via hole.
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