Electronics Forum | Thu Oct 24 13:32:03 EDT 2002 | russ
There are many factors that will affect post soldering height. Lead shape/type, pad geometry, fillet formation, etc... You will need to measure each type of component before and after reflow. Russ
Electronics Forum | Mon Nov 13 13:49:16 EST 2017 | slthomas
Preemptively you can apply Kapton tape to protect the gold fingers during reflow. I think that's what most people do. After the fact, there are services available to clean them up but as it was described in another thread here, it is not in-expensiv
Electronics Forum | Mon Nov 13 21:31:11 EST 2017 | slah6678
Hi David, thanks for reply We did doing some study, most properly this problem was due to reflow process. Any thing that we can do for the reflow profile ? slow down the ramp up rate or .....
Electronics Forum | Wed Sep 16 13:32:05 EDT 2009 | davef
Questions are: * What is the solderability protection on the pad that changes color? * What is the distribution of this issue?
Electronics Forum | Wed Jan 12 10:41:20 EST 2011 | padawanlinuxero
Hello guys ! I have a problem, I am finding some blow holes in the solder join in a resistors pad, can this be because of high humidity in the board? does baking the boards fix the problem? thanks
Electronics Forum | Wed Jan 12 20:18:14 EST 2011 | Jacki
How many % were affected? If a few,it can be caused bcoz of PCB coating. We had encountered it and PCB house replaced for faulty boards. Since then, we do test first if we hve to solder PCBs from this PCB house.
Electronics Forum | Fri Jan 21 11:00:56 EST 2011 | xps
Hi, in my experience, the humidity is trapped in the solder paste. Otherwise you can also try to : adjust preheat profile, and /or increase paste viscosity, and /or increase paste metal content (they are the most common causes).
Electronics Forum | Mon Nov 13 21:27:02 EST 2017 | slah6678
Hi, thanks for reply. Kapton tape is costly and it may create another handling issue. BTW can you share the thread for the cleaning process ?
Electronics Forum | Tue Nov 14 15:48:18 EST 2017 | slthomas
Yes, thanks for bringing up that point, DaveF. All polyimide tapes are not created equal, and in my experience Kapton has always worked for this application. The "better deal" has not, ever.
Electronics Forum | Wed Nov 15 07:21:58 EST 2017 | stephendo
You don't clean contaminated gold fingers so much as you replace them. I once had the "cleaning" solution. It totally dissolved the gold fingers so that they could be replaced.
