Electronics Forum | Thu Mar 30 21:46:56 EST 2000 | Dave F
Reg: This is copy / paste from draft version of IPC 7095 ( issued May 1999 ) ... 7.3 Assembly accept/reject criteria 7.3.1 Voids in solder joint a. Sources of Voids There can be voids in solder balls, or at the solder joints to the BGA, or at the so
Electronics Forum | Thu Nov 13 10:05:18 EST 2014 | grimus
Hello, I'm fighting with problems of random solder balls that appears after reflow soldering around Pin in Paste component. I'm mounting this component with Pick and Place machine. I'm using solder paste type-3 and this is lead free product. This is
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 | Wed Feb 17 15:56:22 EST 1999 | Tuffty
| Dear Al, | Are these reworked, double-sided boards? | | If you attempt to clean side #2 of double-sided misprint in a "spray" type cleaner, millions of solder balls can be broadcast throughout the same chamber as the populated side #1. Or, if thi
Electronics Forum | Sat Nov 15 05:08:45 EST 2014 | grimus
Same side (component side) if You give me e-mail I can provide You more pictures. I'm making one stroke with same speed (I'm using closed proflow head and DEK printer). 5 mils thickness stencil. Products requirement - 3 IPC Class (75 % and more fill
Electronics Forum | Mon Aug 14 01:29:49 EDT 2023 | calebcsmt
I have noticed on a recent project, the QFN and SOP solder deposits do not seem very uniform and have been leaving little balls, whiskers and icicles of solder paste coming from some pads which leads to bridges. https://imgur.com/a/lqw5RF1 I have u
Electronics Forum | Tue Nov 30 16:35:58 EST 1999 | Dave F
The lead Wade is speaking about is not (technically) in solution. It is in suspension (or someting like that). The lead is solder balls, flakes, and the like that is offal from his soldering process. He needs to filter this material from the waste
Electronics Forum | Thu Oct 26 17:42:29 EDT 2000 | Philip A. Reyes
Hi Mr Paul! Thanks for answering my previous questions. Hope you can still accommodate my other queries. This is about the acceptable criteria of PBGA defects after reflow soldering. 1.What is the allowable (min and max. ball misregistration / misal
Electronics Forum | Thu Feb 24 10:52:41 EST 2000 | JAX
Robert, Here's my recommendation's: Solder paste opening on screen should equal the solder mask opening on board. Stencil thickness at .008" but this should not be your main concern as stencil thickness should be determined by the fine pitch that ar
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
