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
Electronics Forum | Thu Oct 23 23:38:48 EDT 2008 | pathakvj
We have 8 layer HASL PCB. We saw molten solder blobs / balls on op side of assembled PCB. (to check, if this was a bare board problem), We passed bare board as received thru, SMT reflow oven and saw solder balls on top side of board. What could be th
Electronics Forum | Fri Oct 24 06:55:48 EDT 2008 | clampron
Good Morning WS, If you experieced the solder balls after reflow of a bare board through the oven, then the source of the solder is either the oven or the board. I have had boards with untented via's that were HASL'd that had entrapped solder and fl
Electronics Forum | Tue Jul 15 15:46:05 EDT 2008 | slthomas
Can you describe your solder balls...mid-chip solder balls, "splatter" around pads, etc.?
Electronics Forum | Wed Nov 20 09:23:53 EST 2019 | alpha1
We had a board we fought with for a while with solder balls. Checked everything, Stencil thickness at .004, reduced apertures, changed paste 3 times, changed profile 3 times. Finally changed board vendors. Went from HASL to Emersion Gold. Problem sol
Electronics Forum | Thu Jun 22 15:05:55 EDT 2017 | solderingpro
There are several different technologies in the industry today to assist in the out-gassing of flux cores. On automated soldering systems, there are two main types of perforating solder feeders: - Hole Drilling - "V" Scoring By perforating the so
Electronics Forum | Thu Sep 16 15:01:13 EDT 2004 | russ
You may want to either open up the bottom of the vias so they will not "volcano". Or you will want to seal both sides. It never works having one side of the vias masked and the other open with HASL. Russ
Electronics Forum | Tue Sep 14 14:52:22 EDT 2004 | Carol
During processing, the solder in the vias reflows and forms solder balls. PCBs have solder in random PBGA vias from the board manufacturer.The manufacturer says this is a result of the HASL process and is unavoidable. We use HASL finish, multilayer,
Electronics Forum | Tue Sep 14 19:47:16 EDT 2004 | davef
use something other than HASL. "The rest of the world seems to be processing with no problems..." [Hello!!! Earth to Carol. This is a test.] Things you are considering could be more trouble than they�re worth. "1) Reduce via hole size" [If you re
Electronics Forum | Mon Dec 02 16:01:15 EST 2002 | russ
If you can, attach athermocouple to the locations where you are getting solder balls. A previous product I had showed the same thing and we found that we had inadequate preheat leaving the liquid flux to splatter when it hit the wave. It could aslo