Electronics Forum | Tue Jul 07 08:42:49 EDT 2009 | ewchong
kpm, you are probably right. under magnification those two pads show some exposed copper which means that they were contaminated or had insufficient solder paste before reflow.
Electronics Forum | Wed Jan 26 14:33:14 EST 2011 | remullis
Exposed copper on the edges of boards is what I'm refering to. could be a potential shorting issue in your housings. Just depends on the application. We have cut into ours and use humiseal to dress them off. Rich
Electronics Forum | Tue Dec 14 12:00:34 EST 1999 | Kris Wiederhold
We recently reduced our standard aperture reduction to aid in the reduction of solder on gold defects. Since this reduction in aperture size, we have been experiencing exposed copper at the end of the component pads. The heel and toe joints are per
Electronics Forum | Wed Nov 17 10:03:29 EST 2010 | scottp
Instead of a minimum thickness, we require no exposed copper or SnCu intermetallic. We've been having a lot of trouble lately with suppliers of SN100 HASL boards giving us pads with very irregular solder deposits with areas of exposed intermetallic.
Electronics Forum | Wed Feb 21 21:01:57 EST 2007 | davef
Yes. Heat reduces OSP solderability protection thickness. For instance, many OSP are shot at the end of the first reflow pass and the exposed copper is free to oxidize. If you're speedy, you can pull-off the second reflow cycle before the copper g
Electronics Forum | Wed Apr 15 15:24:40 EDT 1998 | D.Lange
| I am looking for a product to repair PCB mask (seal exposed copper) and fill Gouges in pcbs, any suggestions? Try this stuff no mix no mess comes in green and clear and maybe other colors. Dries readily at room temp and is in pen form for easy disp
Electronics Forum | Thu Feb 12 17:14:49 EST 2004 | Jim
Replying to mine own thread for clarification. We are having some issues with solder mask shifts on memory boards using fine pitch BGAs. At times the etch to etch distance does not leave room for a solder mask annular ring to be shifted or it will c
Electronics Forum | Thu Mar 30 08:48:37 EST 2006 | russ
So you have solder balls at the outer edge of the part right where the pad goes underneath? If so you just have too much solder but I wouldn't worry about them. the solder usually does not wet to the edges of these parts because of the exposed copp
Electronics Forum | Thu Mar 25 14:30:29 EDT 2010 | boardhouse
I would not use the product. Solder balls on a massive scale would be one issue due to all the exposed copper. Throw them out, it will be cheaper and less of a headache. I would also question your board shops quality control or lack of for letting
Electronics Forum | Mon Sep 17 05:48:10 EDT 2012 | stivais
Hi Ben, Yes, this could be the reason but have you ever seen solderability issues for (new) boards with LF-HAL surface finish? I have seen this only if there are surface finish quality issues for bare boards (exposed copper etc.). In this case we di
