Electronics Forum | Sun Dec 31 07:31:40 EST 2006 | davef
Thoughts are: * Eliminate solder spotting on gold fingers through process improvement in broard handling, printing paste control, and reflow recipe development. Search the fine SMTnet Archives for previous discussions. * Dispense or print a reflow te
Electronics Forum | Thu Jun 08 10:52:37 EDT 2000 | rolandos1
Hello, My name is Rolando and I want to know more about gold fingers protectors. Our current problem is on SMT line which is used with one board with gold pads and while normal production we get solder paste contaminations on these pads, recently o
Electronics Forum | Sun Sep 26 05:27:35 EDT 1999 | Edmund
i had a problem here, during the wave soldering process, we apply a water soluble mask on the gold finger to protect it from contamination. But after washing, there is still some mask left on the gold finger. Can anyone pls advise is there any parame
Electronics Forum | Wed Jan 22 10:24:23 EST 2014 | cyber_wolf
No matter how good your process is, you will get solder on the gold fingers/lands unless they are protected. We have proven that solder will get on the gold fingers in the reflow oven. How that happens....we arent't 100% sure...there are a lot of the
Electronics Forum | Sat Mar 14 09:12:59 EDT 2009 | davef
First, there is no good justification for getting solder on gold fingers. Second, it is well known that solder on gold fingers is unacceptable. So, shipping boards with that condition indicates sloppy quality practices at your CM. Third, that being
Electronics Forum | Sun Sep 26 11:54:06 EDT 1999 | Earl Moon
| i had a problem here, during the wave soldering process, we apply a water soluble mask on the gold finger to protect it from contamination. But after washing, there is still some mask left on the gold finger. | Can anyone pls advise is there any pa
Electronics Forum | Wed Jun 30 17:58:01 EDT 1999 | Boca
| My guess would be trapped flux continuing to be active after soldering. Is the tarnish there immediately after exiting the machine? Do you remove the mask and wash right away? If the solder is reflowing under the mask on the component side it wo
Electronics Forum | Wed Jul 05 17:06:36 EDT 2000 | Michael Parker
Patrick- You have not given enought detail of the type of discoloration. Is it "white residue"? Can it be "rust" colored? Whatever it is, you fab supplier needs to be called in immediately and give you an exact reason for this failure. Just rubbing
Electronics Forum | Thu Jul 01 14:47:10 EDT 1999 | Tony
| | | My guess would be trapped flux continuing to be active after soldering. Is the tarnish there immediately after exiting the machine? Do you remove the mask and wash right away? If the solder is reflowing under the mask on the component side
Electronics Forum | Fri Jul 02 10:06:17 EDT 1999 | John Thorup
| | | | We are wave soldering some fabs with a lot of unmasked trace area along the edges. The trace area is solid copper covered with tin / lead, no masking, no components along the edges, same on solder side and component side (goofy board design)
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