Electronics Forum | Wed Jan 14 08:28:46 EST 2004 | davef
Search the fine SMTnet Archives for background on solder on gold fingers. As we recall: * Paste selection * Proper reflow recipe tuning ... are important.
Electronics Forum | Fri Jul 23 14:41:41 EDT 2004 | Steve Stach
Dear JSK, It sounds like the root causes of your problem are two fold. First, excessive heat will polymerize the abietic acid found in rosin forming neo-abietic diamers and polymers which are much less soluble than the parent monomer. There are
Electronics Forum | Thu Jul 07 07:18:50 EDT 2005 | davef
Sounds like you need to turn-up the dial of your oven. Solderabilty protection finishes on components are changing, whether it makes sense or not.
Electronics Forum | Thu Jul 07 18:03:27 EDT 2005 | russ
Sarag, FYI tombstoning is a functional failure. Tombstoning is where one end of the component is not soldered and is in the air above the board/solderjoint surface. You may be thinking of billboarding (part on its side with both ends soldered down)
Electronics Forum | Thu Jul 14 09:26:30 EDT 2005 | saragorcos
Hello Lloyd, I have posted your picture in my photo library for all to see - you can find the page at http://www.residues.com/circuitree_pictures.html Hopefully that helps! Sara
Electronics Forum | Mon Jul 25 18:54:10 EDT 2005 | Brian
Exactly. We bring the paste apertures closer together, so that the part sits more in the center of the paste. As a CM, our customers do not always accept our recommended design changes, so we use this method to reduce our tombstoning if the pad geo
Electronics Forum | Wed Aug 10 08:53:45 EDT 2005 | jh0n!
Wasn't aware of that. We're using a no-clean with RF pcbs, and that's something to bear in mind for the future - thanks.
Electronics Forum | Mon Feb 05 11:31:37 EST 2007 | davef
While you're waiting for others to reply, look here: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=19507
Electronics Forum | Mon Jun 19 09:47:23 EDT 2017 | georgetruitt
You have a lot to think about! What does the flux manufacturer recommend as far as specifics like water temp or pressure? Do they recommend high temp di-water a detergent or saponifier? Do you currently have a cleaning machine, batch cleaner or inl
Electronics Forum | Mon Sep 28 19:07:47 EDT 1998 | Steve Gregory
| I have had some field failures returned recently, the boards had flux contamination under the components in a sensitive area, Nothing really visible until the component was removed, and the board had no evidence of rework of any type. Is it poss
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