Electronics Forum | Thu Jan 27 15:13:26 EST 2005 | jbrower
Hi Tom, Thanks for the compliment. I've been researching and planning for the time that my company would go lead free since late in 1999. I hear you there, how do we know that the component is lead free. Baring a leap of faith with your vendors, I
Electronics Forum | Fri Jul 29 19:12:30 EDT 2005 | Jason Fullerton
In the true sense of the term, tombstoning can only occur during reflow. Now, if your solder joints are cracking during thermal cycling and opening on one end you still have a problem - it just isn't "tombstoning". What laminate are you using on yo
Electronics Forum | Wed Sep 07 10:34:52 EDT 2005 | PWH
Have experienced this on a few different cap. parts. Agree with other postings. Following are solutions to problems we have had: 1) Cracked cap too close to board edge per IPC spec. Designer replaced part with 3 caps in series to eleviate stress
Electronics Forum | Thu Jan 05 11:23:49 EST 2006 | samir
Grant I'm gonna have to go ahead and sort of disagree with you there. The studies that I've been reading from various BGA Manufacturers have identified insufficient homogenizing / coalescing of the Sn/Pb Paste with the SnAgCu balls. Ball not touchi
Electronics Forum | Wed Oct 04 09:55:51 EDT 2006 | borgie
Hi. I have product in lead containing process that consist lead free BGAs and also big ceramic BGAs with high temperature bumbs. Pcb tends to bow in a reflow profile, since I need long preheating times and relatively high peak temperature to melt BG
Electronics Forum | Fri Apr 20 07:54:25 EDT 2007 | Bob R.
I'm in the high reliability (exempt) sector and have thermal cycled hundreds of boards in the past few years. As far as which is more reliable, SnPb or SAC305, my data is similar to what the technical literature is saying, "It Depends". In low stra
Electronics Forum | Fri Nov 16 08:47:04 EST 2007 | rgduval
Fractured parts that we've seen at reflow in the past are related to trapped moisture in the part, out-gassing at temp, and fracturing the part. I have seen this on ceramic resonators in the past; don't know why this type of part seems prone to this
Electronics Forum | Tue Mar 04 08:56:38 EST 2008 | tonyamenson
I talked to a solder paste chemsist and found out a few things. From above (Dave F) states a test for solder paste involving reflow on a non-wettable surface. Commonly known as the solder ball test this test is performed all the time by paste manufa
Electronics Forum | Sun Jan 18 09:20:26 EST 2009 | davef
We're not sure of the condition of your solder paste. So, afte 24 hours, if it's: * Unused, in a reclosed container, maybe a week of life depending on the environment * Used, scrap A simple coalescence test can quickly determine the condition of sol
Electronics Forum | Sun Jul 26 06:31:07 EDT 2009 | hohk
Hi everyone, I need to connect a cylindrical disc device (piezo ceramic sensor) to the PCB trace without using high temp solder. I plan to use "3M™ XYZ-Axis Electrically Conductive Adhesive Transfer Tape 9719" to connect the device to the PCB trace
