Electronics Forum | Sun Feb 06 12:04:06 EST 2005 | ddhanashekar
can some one give me some suggestion to solve the problem. we are using cooksun/alphametal rma9086 paste for our screenprinting. after the reflow we see lot of solder ball on the board. we have maintained the exact profile given by the manufacurer. w
Electronics Forum | Mon Aug 13 11:05:18 EDT 2007 | saaitk
Would I be correct in assuming that the solder used to attach the BGA ball to the device body should have a higher liquidous point that the solder used to attach the device to the board. If the peak reflow temp for SnPb is around 225 deg should the b
Electronics Forum | Fri Aug 24 11:03:15 EDT 2007 | hussman
I agree with Joris. But to add to his comment, the type of finish also has a direct affect to your wave solder process. Going from a gloss finish to a matte finish may help a lot. As for humidity affecting your wave - I doubt it. I use a water
Electronics Forum | Tue Jan 15 08:50:07 EST 2008 | ck_the_flip
Based on past, actual, hands-on experience, I have found that the PCB mask finish makes a HUGE difference in solder-balling. Glossy has different surface tension and peelback characteristics than matte finish (ie glossy sucks). http://circuitsassem
Electronics Forum | Tue Aug 17 13:36:17 EDT 2010 | hegemon
Since you have home plated the apts and done solder reduction, I would take a look at your soldering profile. We have run into this before when running no-clean and found that reducing the initial ramp rate to the flux activation was a help in the
Electronics Forum | Tue Aug 17 14:34:27 EDT 2010 | davef
Comments are: * Too much paste ... reduce it more. * Do not let a traces run between small discrete pads or the heat of reflow will pull a ball to the trace, we can repeat this. * Change the placement height on chip parts to reduce solder spread / mu
Electronics Forum | Thu Aug 19 16:03:04 EDT 2010 | kpm135
Are you reusing your paste or putting down new every time? I've seen solder balls before when operators try to use the paste past the recomended stencil life. I've also seen it happen with a bad batch of solder paste from a vendor.
Electronics Forum | Fri Mar 25 05:33:18 EDT 2011 | Nigel, RAKON
We have the occasional solder fine but the main issue I have is with small - large balls of solder around an 0402 capacitor. Our LF paste data sheet states a %rH of 25 - 70, I have recorded an average for March of 14.9 - 38.5 %rH. Every other requirm
Electronics Forum | Mon Apr 02 17:51:02 EDT 2012 | swag
Almost sounds like a part fell in the pot, exploded and burned into powder. We had a part get into our pot somehow and produced powder dross + other contaminates (no solder balls, though). The ring around the pot was very difficult to remove but wa
Electronics Forum | Fri Jul 27 13:51:53 EDT 2018 | vlad_saviuk
Hi, have some question: during solder paste printing I'm faced with problems on the edge of the PCB - solder balls on gold pads. During analisys we checked everything - change squeegee preasure, different cleaning cycles, squeegee speed - no effect.
