Electronics Forum | Mon Apr 19 10:52:05 EDT 2010 | esca
Hi, if you want to verify the gold contamination, is mandatory to use the XPS and FTIR analysis, but is difficult think about a gold contamination from 3 different manufacturers. Do you have cleaned the PCBs after an erroneous screen process ? If no
Electronics Forum | Thu Jan 27 04:02:00 EST 2011 | richiereilly1
Hi, We had a similar issue to this. When we examined the boards at x-ray there were no apparent defects, We sent the boards for Dye and pry testing and we found that there were crack or gaps between the paste on the PCB and the BGA ball. basically th
Electronics Forum | Fri Aug 03 14:55:26 EDT 2012 | davef
Not the best situation in the world, but you know that. Check with printer equipment suppliers [eg, DEK, MPM, etc] for a product called "Stencil Clean Wipes." Back in the old days, we'd: * Wipe the stencil with a solvent soaked wipe * Put the sten
Electronics Forum | Thu Aug 30 20:35:51 EDT 2012 | davef
A common bottomside heater configuration is IR-Convection-Convection. One of the big advantages of the IR zone is its ability to allow the flux carrier to spread and dry slowly before the board reaches the convections zones, which can blow wet flux c
Electronics Forum | Fri May 17 08:43:46 EDT 2013 | fredcalkins
If you have Flexhead nozzles you need to be careful that whatever solvent you use does not attack the gasket adhesive. I might try a couple of drops of a spray like WD-40 or LPS. Let it soak for a few minutes and blow it out with compressed air. Repe
Electronics Forum | Fri Jun 07 10:02:01 EDT 2013 | sarason
In thirty years of Electronic service I have never had problems with moisture in boards when hand soldered. I have worked on boards in boxes for defense through industrial control, joy rides etc. Sometimes they some back buried in half an inch of dus
Electronics Forum | Sat Aug 29 21:42:46 EDT 2015 | sarason
When I made my previous reply, I don't think I was very clear in what I said, so like any politician I will rephrase my response to the question. My intent was that the board didn't have enough soak time leading up to final reflow. So what was happen
Electronics Forum | Wed Mar 01 02:10:05 EST 2017 | soldertraining
Hi! I am Bob and pls forgive me if technical words I use are wrong. What may cause the BGA solder pad lift before or after reball? I am having problems where solder pad lifted during removal of bad solder ball. It also occurred during reball, where t
Electronics Forum | Thu Jun 02 22:40:13 EDT 2016 | slouis2014
Hi, yes have a few experiments initially i tried to increase the solder volume but component pin have insufficient solder. 1. The solder coverage do you calculate it by solder volume or solder area. 2. if i would achieve as you recommend 50-60 % woul
Electronics Forum | Tue Feb 07 12:26:14 EST 2017 | westshoredesign
Oh yeah, so we have a auger valve similar to that on one of our other machines that we use for dispensing SMT glue, and solder paste also. We have a conditioner that we flush it with at EOD when in use, then we just let it sit idle with the condition
