Electronics Forum | Mon Feb 14 12:05:24 EST 2000 | Dave F
Masdi: Are you sure you have your washer set-up correctly? We never have problems with solder balls. Ta. Dave F
Electronics Forum | Mon Jul 18 12:24:53 EDT 2016 | oleksz
Some people involved in PCB assembly process claim that SMD components reflow soldering problems are often caused by traces running under a component. According to this claim, trace (or any copper) covered by solder mask and placed under SMD componen
Electronics Forum | Mon Jul 18 12:25:30 EDT 2016 | oleksz
Some people involved in PCB assembly process claim that SMD components reflow soldering problems are often caused by traces running under a component. According to this claim, trace (or any copper) covered by solder mask and placed under SMD componen
Electronics Forum | Fri Feb 11 08:51:45 EST 2000 | HMAL
Dear Masdi, Perhaps you should check again your screen print process. Small amounts of solder paste under stencil can cause your problems. This paste is from previous printed pcb. When printing next pcb this paste attachs to places that it doesn't
Electronics Forum | Wed Feb 07 16:14:54 EST 2001 | Antonio
I've recently read a posting here which said that the person was trying to reduce solder balls. One of the things the person had done was to adjust the reflow profile so as to be hotter and longer in the reflow state. Am I wrong here? I thought th
Electronics Forum | Thu Jul 05 10:45:01 EDT 2001 | dougie
Steven, There is a load of info on this if you check through the archives. Quick pointer though are: Solder balls are caused by paste creeping under the component at placement. The part is placed and the paste is squashed under the component, when t
Electronics Forum | Thu Jan 09 20:52:02 EST 2020 | Mike Konrad
If the world was a perfect place, I would recommend preventing solder balls in the first place. While low amounts of solder balls are common, a high volume of solder balls are problematic to a cleaning machine (batch or inline). Solder balls may beco
Electronics Forum | Thu Jul 19 08:00:03 EDT 2001 | doctord
Solder balls or mid chip beads? Remember IPC classification for Class 2 allows mid chip beads encapsulated in flux. Usually on R's and C's first thing I would do is verify .006 laser stencil 10% reduction and the most critical, The paste must be on t
Electronics Forum | Thu Feb 08 09:07:22 EST 2001 | Hussman
OK, without knowing the specifics, why does everyone blame the oven? Most solder balls occur around R's and C's in almost every shop I've been to. The best place to start looking is the screen printer - not the oven. Sure the oven is the last proc
Electronics Forum | Thu Jul 12 10:32:59 EDT 2001 | Hussman
Wow, what a string of answers and nobody brought up the easiest way to eliminate solder balls. Yes, the paste being squished under the part does reflow and work it's way out to the side during reflow. I did a 5 week study on this (when I was a bori
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