Electronics Forum | Tue Aug 21 20:52:06 EDT 2007 | davef
There is not standard for the force to pull an axial lead from a soldered connection. ".....IPC does not have pull tests in any of its standards, and some reliability experts would prefer to keep it that way, pull tests are commonly used by some lea
Electronics Forum | Sun May 26 02:06:39 EDT 2019 | jlawson
Placement force can cause chip cracking-micro cracks also. As machines are getting faster they tend to not control force other than spring pressures and z displacements. There are some machines that have full closed loop place pressure control , but
Electronics Forum | Fri Dec 01 10:58:48 EST 2000 | PeteC
JM, Be sure to include in your analysis to check the caps before placement. We had some problems w/ EPCOS caps being already cracked in the tape. I don't know about max force permitted for a given cap.
Electronics Forum | Mon Feb 24 20:51:52 EST 2003 | davef
Ryan, You are spot-on with your analysis of the 'flattened' glue deposits. How about this for a different approach[es] in explaining your method for removing caps from your board? * George Verboven has speculated here on SMTnet that the downward fo
Electronics Forum | Fri Dec 01 07:28:37 EST 2000 | JM Lasserre
I just started an analysis concerning broken capacitors (0603 ceramic). My first question concern the standard used to determine the maximum force a capacitor 0603 can support on a pcb. Some capacitors suppliers use the die sheer test of MIL-STD-883
Electronics Forum | Thu Oct 24 12:09:31 EDT 2002 | slthomas
Have you looked at cross-sectional analysis? If they can provide you details of where the failures are occurring, maybe you can chop one up and see exactly what's going on? We've done it once for our own engineering department and the results (not
Electronics Forum | Thu Aug 17 17:36:08 EDT 2006 | slthomas
I don't have any data (haven't tried this), but it doesn't take much thought to see that determining the risks associated with simultaneously applying compressive and rotational forces to the end of the barrel, not to mention chewing up the copper, i
Electronics Forum | Wed Mar 12 23:00:10 EDT 2008 | davef
You can say: The pad was lifted after reflow and prior to the dye and pry failure analysis. When we see lifted pads, we think: * That's a good solder connection * Either it took a lot of force to lift that pad or the fabrication of the board in the
Electronics Forum | Tue Aug 01 09:42:07 EDT 2000 | Gary
The Technical Services Group at Alpha Metals has spent a fair amount of time looking at wave soldered Pb-free connections. We too have observed fillet tearing, fillet lifting, and pad lifting. I have concluded that without major changes in the mate
Electronics Forum | Wed Dec 20 09:41:52 EST 2000 | blnorman
Ideally we want to mix the same lot numbers in a repackaged tube. Once again, these are partial tubes that have been thrown away. If the ratio is right to begin with the only change would be due to air exposure. Semco makes a TC seal which, if we