Electronics Forum | Wed Jan 14 13:38:38 EST 2009 | vleasher
I am attempting to identify a good epoxy to hold on larger parts on thru the reflow process for the opposite side. We currently dispense epoxy prior to second reflow on the corners of the component because the epoxy we use cures before reflow and doe
Electronics Forum | Fri Jan 16 13:11:27 EST 2009 | evtimov
HI , A LOT OF SIMILAR ISSUES WERE DISCUSSED LATELY. MOST OF THE TIME THE PROBLEM IS IN THE BOARD FINISH. THE BEST OPTION IS GOLD FINISH(ENIG). MAKE A SAMPLE AND TRY IT WITH BOTH PASTES YOU HAVE. ANOTHER THING I DID BEFORE AND IT HELPED ME PARTIALLY
Electronics Forum | Tue Jan 20 11:54:12 EST 2009 | smt_guy
Is this Corrosion? We found our boards with this issue 45 days after they were delivered to us from supplier. The board finish is HAL Leaded. But I noticed that the corrosion like issues are coming form the tiny via holes with SILVER EPOXY FILLING.
Electronics Forum | Tue Jan 20 17:51:24 EST 2009 | davef
We'd guess that since your board fabricator could not remove this stuff with it's HAL-leaded process, you're unlikely to remove it with your soldering process that is likely to be pansy-ass compared to your fabricator HAL process. Hey, why not run a
Electronics Forum | Tue Mar 31 05:26:14 EDT 2009 | d0min0
Hello, we had similar problem in the past - when we had to change PCB supplier from a batch of hundreds of boards (NiAu plated, SnPb process) we got 2-3 boards with paste wicking to components leads what we did, was to check the thickness of gold on
Electronics Forum | Thu Mar 12 06:23:27 EDT 2009 | gregoryyork
Thanks Nicoleta It is nice to hear the problem is solved and this is a massive problem in the industry especially for Lead Free. It is easy for a supplier who doesn't understand to blame incompatibility just a quick way out but doesn't fix anything
Electronics Forum | Tue Mar 03 14:07:07 EST 2009 | macisaint
I'm having shorts appear on my QFN packages between pins, usually only after a week or so of power-on operation. The shorts are 1K and slowly down to hard shorts over time. Typically a defective part will have failures on multiple pins. I tried havi
Electronics Forum | Thu Mar 12 06:37:48 EDT 2009 | gregoryyork
I agree you are too cold for the profile get it up to 230C and possibly allow it to dwell a little longer in preheat as opposed to pushing up the reflow zone only. Sn90/Pb10 melts at 220C so 2C hotter than your profile so you are reliant on it alloyi
Electronics Forum | Wed Apr 22 22:51:42 EDT 2009 | rkevin
I was using Indium 8.9 HF and AIM 257-2 was far superior in reducing voids. Just wait till you have a problem, if you have less than 10 lines running 24/7 don't expect a call back from Indium's Tech Support. It's been a couple weeks since we swithed
Electronics Forum | Mon Apr 06 11:46:10 EDT 2009 | c111
I agree the longer soak will help provided you are not applying to much heat/time to the board now. -are the pads that lift connected to anything? This has happened to me in the past where un-connected pads would come of far easier than those connec
