Electronics Forum | Wed Jun 03 13:51:57 EDT 1998 | Dave F
Hello: BACKGROUD: SMT components soldered on the top-side of boards that also require wave soldering have the potential to reflow during wave soldering. Reflowing these components during wave soldering is not good. It can cause cold joints, opens
Electronics Forum | Thu Feb 21 16:57:02 EST 2008 | flipit
If the vias are large and don't always tent, you can have your pcb supplier double mask the pcb. I do this for COB assembly sometimes because the globtop wicks through the vias and also causes air bubbles in the globtop.
Electronics Forum | Thu Mar 03 08:06:36 EST 2011 | scottp
I've seen this with through hole via in pad with soldermask plugging from the opposite side. Baking the boards solved it. Not using such a horrible via in pad method would also have solved it, but that wasn't an option. Is this ball sitting on a v
Electronics Forum | Thu Jun 02 07:27:11 EDT 2011 | scottp
You need to post a picture or describe your geometry better. Is this a through hole via in pad or is the via offset from the pad with no soldermask in between?
Electronics Forum | Fri Oct 30 08:24:12 EDT 2009 | rajeshwara
thnx davef & all With the help of all at last i solved the problem , The vias are not caped from bottom , so solder paste draining through the via to the floor which creates voids between IC ground pad and e-pad. Tnhx all again
Electronics Forum | Thu Sep 21 10:34:20 EDT 2006 | Kerwin Hooshey
Is there an ICT probe style that can pierce through tented (closed) via's?
Electronics Forum | Mon Sep 24 18:00:58 EDT 2001 | jagman
Does anyone know the cause(s) of solder flowing through a via to the other side of board during reflow causing solder bumps on opposite side? Is this mainly a design issue or could it be process related? Any help is appreciated.
Electronics Forum | Tue Mar 07 08:48:55 EST 2006 | samir
Our ICT Guy here at my company loves to use lots of via holes as test points - via holes which are 0.040" diameter, and spaced at 0.004" edge to edge spacing! He doesn't like to tent the via's either, so I always battle via-to-via shorts at the wave
Electronics Forum | Mon Nov 05 02:51:48 EST 2007 | omidjuve
our boards have many smd pads that has vias under them so when the screen printer wants to print the solder paste on it , it will penetrate through the via to the bottom side of the board and cause many problem for us . i want to know that is it sta
Electronics Forum | Fri Jun 11 03:50:39 EDT 2004 | Scott B
We currently have an issue with via's in pads which we have been living with for some time. The problem has now escalated with the need to increase the via hole size to achieve PCB fabricators aspect ratio's. We are now not only experiencing solder d
