Electronics Forum | Wed Sep 15 17:31:40 EDT 2004 | GS
Once you verified for correct profile ( consider CTE mismatch) make sure before you remove PBA from fixture, the temperature is almost at room temperature. If by removing PBA from fixture,and the PBA gets a little bent (warped) just in the area where
Electronics Forum | Fri Sep 17 23:19:07 EDT 2004 | KEN
What is the component ball co-planarity spec? I have encountered many ceramic and ASIC devices that specify 7 mil max. If your stencil is 4, 5, 6 mil you WILL eventually have an open joint. You must deposit solder greater than or equal to your cop
Electronics Forum | Thu May 18 11:00:51 EDT 2006 | Chunks
Thanks Doctor - as always, you're right. I must've been typing with my mittens on. It's starting to get cold on this part of the planet these days. I wasn't blaming anyone, just trying to take a few questions marks away so "we're" left with the an
Electronics Forum | Mon Jan 19 14:54:38 EST 2004 | cyber_wolf
How did you come to the conclusion that you are having a cold joint problem. Just by appearance ? As Dave stated if you have any of the metals that he listed in the joints they will appear to be dull and grainy sometimes. But... Dave, I will have t
Electronics Forum | Wed Jan 28 21:47:56 EST 2009 | padawanlinuxero
Hello! I am having trouble with the new changes from lead joint to lead free joint, we are working on change to lead free, I am using a 3 zone oven reflow, the zone temps are : zone 1 zone 2 zone 3 (top and bottom) 128 208 260 th
Electronics Forum | Tue Apr 11 10:30:46 EDT 2000 | Jeremy Smith
I am having a problem with some joints on a 100 pin pqfp and few different soics on one particular board. When viewed a 8x with a "Mantis" inspection scope the joints look as though they wetted to the ic leg but when probed the leg will pop loose.
Electronics Forum | Wed Jun 08 23:04:26 EDT 2022 | SMTA-64387544
Au thickness of 0.125 um should not cause solder joint embrittlement. Also, PCB fab should offer Au thickness range between 0.05-0.075 um for better process control and reliability. Higher Au thickness may suggest black pads leading to solder joints
Electronics Forum | Thu Dec 09 17:45:27 EST 2004 | davef
You're correct. There is no criteria for no-lead, but there none for SnPb, either. Solder joint strength in pull/shear will vary with lead geometry, solder volume, lead metal/metallization, the way the test is done.
Electronics Forum | Tue Nov 28 09:21:58 EST 2006 | Michael Sanders
Is anyone aware of any articles, white papers, etc., that discuss the gap between the lead and the pad after a SM joint is soldered? In particular, I am looking for a formula for that "gap" for various components.
Electronics Forum | Tue Nov 28 20:12:41 EST 2006 | davef
We don't have a gap between the lead and the pad after a SM joint is soldered. On our boards, this space is filled with the solder intended to attach the component to the board. How high do components sit above the surface of a board? Most people a
