Electronics Forum | Wed Aug 16 14:30:31 EDT 2006 | slthomas
What do you mean by "near the pad of SMT component"? The end of the pad, side of the pad, or perhaps adjacent to the part body, between terminations? One solder ball per component, or many, perhaps of different sizes?
Electronics Forum | Wed Oct 04 16:18:06 EDT 2006 | cw
My Peak ~ 228-230C (customer wants to see this temperature). solder ball size - 20mil diameter Please advise ASAP. Thanks a lot!!!
Electronics Forum | Fri Oct 20 10:15:13 EDT 2006 | wrongway
mid chip solder balls we had that trouble for awhile we went from a 8 mil thick stencil to 6 mil stencil and did some home plate style of cut outs in the stencil for the 1206 caps and resistors it seemed to fix our mid chip solder balls
Electronics Forum | Wed Nov 29 01:12:12 EST 2006 | callckq
Dear Davef, Thanks for your input...The crack happen at the pad/solder ball interface..Pls review the new thread that I post just now with title called "BGA BALL CRACK AT PAD/SOLDER BALL INTERFACE" Thanks!
Electronics Forum | Wed Dec 06 21:36:13 EST 2006 | davef
It's surprising that you have that much copper. Copper contamination of leadfree is usually tolerable up to 1%. So, the copper is moving from the pad to the solder ball. Right? If that's correct, the pad requires a buffer material between it and
Electronics Forum | Thu Aug 23 22:41:54 EDT 2007 | davef
Water soluable fluxes are quite hydroscopic. If you keep RH below 50 percent, solder balling caused by humidity should be minimized.
Electronics Forum | Fri Aug 24 09:29:08 EDT 2007 | jgrootkoerkamp
Solder balls with wave soldering can have different causes. The two most important are the solderresist and the flux. I have similar problems, after changes the flux type 90% off all solderballs are gone. KR, Joris Groot koerkamp
Electronics Forum | Fri Aug 24 12:39:59 EDT 2007 | hussman
I would say no, unless your machine is in extremeconditions. You may want to check your flux / preheat out as well. If you are leaving a lot of flux on the board at wave, it may be boiling - which can cause solder balls.
Electronics Forum | Thu Oct 16 08:41:21 EDT 2008 | davef
We don't associate solder balls with no-clean flux and humidity. For solder balls with no-clean flux, we'd rather have you thinking about: * Paste selection * Aperature size * Paste print process * Reflow recipe
Electronics Forum | Thu Oct 30 19:59:05 EDT 2008 | gregoryyork
solder ball was caused by hasl process not reflow. seen before many times, look around wells of smt on bare boards should be more of them
