Electronics Forum | Tue Apr 27 17:37:30 EDT 2004 | Ren�
We have switched over form Indium's nc-smq92 to > nc-smq92j and are experiencing a ton of solder > balls. Even if the print is dead on we still seem > to be getting them. We never seemed to have this > problem with old paste unless the print was
Electronics Forum | Thu May 24 08:55:25 EDT 2007 | ck_the_flip
Here's some quick things to look for: 1. Does your solder paste feel like concrete, does it roll-up into your squeegee blades, and stick to your stencil? If so, your problem is the solder paste. The mixture of powder and flux, or metal load is ou
Electronics Forum | Fri Apr 23 08:20:25 EDT 2004 | babe
Sometimes solder balling is related to oxidized paste or paste that has sat on the pcb too long before reflow. Mostly it is related to process, sorry... Too slow or too fast of a reflow ramp rate. Heating up an assembly too quickly will not allow the
Electronics Forum | Wed Apr 28 09:15:15 EDT 2004 | smtpro
Yes we are using a 7 zone and a ramp to spike. How do you handle your solder paste and what printing methods do you use?
Electronics Forum | Tue May 22 20:27:34 EDT 2007 | davef
What are the area and aspect ratio of the apertures that clog? When you print, you should be able to fit at least 4 of the mean sized solder sphere across the width or diameter of your smallest apertures.
Electronics Forum | Fri Apr 23 07:50:50 EDT 2004 | smtpro
We have switched over form Indium's nc-smq92 to nc-smq92j and are experiencing a ton of solder balls. Even if the print is dead on we still seem to be getting them. We never seemed to have this problem with old paste unless the print was way off. Is
Electronics Forum | Wed May 12 08:35:20 EDT 2004 | solderpro
yes this paste is a pain in the paste.... there are very few reasons for solderballs, component to pad ratio and placement.... solder paste control, using a mixer, not hand mixing, checking viscosity and temp..... or simply and bad profile and your
Electronics Forum | Tue May 22 11:03:11 EDT 2007 | Michelle
We now have an AOI in our process after printing and have noticed that all the small aperatures are getting clogged by solder paste. Mainly on all fine pitch parts. We are using Kester ws R562 SN63/PB37 mesh -325+500 90% metal. It was manufactu
Electronics Forum | Mon May 17 02:06:57 EDT 2004 | johnwnz
Look here: _a class=roll > href="http://www.aimsolder.com/techarticles/tech%2 > 0sheet%20BGA%20voiding-%20reducing%20through%20pro > cess%20optimization.pdf" > target="_blank"_http://www.aimsolder.com/techartic > les/tech%20sheet%20BGA%20voidin
Electronics Forum | Thu Dec 10 09:06:47 EST 2009 | stepheniii
Just how cold do you store your paste? And what are your solder paste reps like? Here they fall over each other giving support for their paste. And have you seen the problem with flux separation or have you only heard about it?
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