Electronics Forum | Thu Feb 24 14:58:11 EST 2000 | Greg denham
Does anyone have any information on baking boards to remove moisture before reflowing and waving assemblies? I've been told that we should do this to stop such problems as delamination of boards, blow holes, solder balls, etc. I don't know have any e
Electronics Forum | Thu Feb 24 18:08:42 EST 2000 | Travis Slaughter
Baking boards, especially multi layer, will help with blowholes and delimitation, but not with solder balls. Normally about 120c for 1 hour or so is sufficient. I usually will not go to this trouble unless a board has proven to be a problem or if th
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
Electronics Forum | Wed Oct 11 09:23:06 EDT 2000 | Roger Squires
Has anyone had any success in finding open circuits (i.e. ball present but not soldered to PCB) under collapsible BGA's using an Agilent HP5DX x-ray tester and the BGA2 algorithm? Can anyone recommend an elongated pad design which produces the neces
Electronics Forum | Mon Jan 22 11:35:16 EST 2001 | kirks
Hey Mike, what do you recommend for PCB cleaning if there was a mis-print during the screen printing process. Currently we are hand cleaning them with a SMT solution but are having problems with solder balls in the via's and joints. What cleaning mat
Electronics Forum | Fri Sep 08 04:45:17 EDT 2000 | PeterB
As per Travis's reply it could be something other than the reflow process. Another good one is if the printed PCB's have been cleaned down due to print misregistration etc.. If not properly controlled paste residues can remain distributed about the p
Electronics Forum | Mon Sep 04 01:01:33 EDT 2000 | Ramot Avichai
Hello Daniel !! You can use a stick vibrator for BGA on IP2 machine. Make a slider in the right shape, and put insert the BGA as a regular component. For the part data use only the contour of the component (ignore the balls). I can asure you that the
Electronics Forum | Tue Aug 22 14:02:02 EDT 2000 | JAX
Caumel, You should be able to find sufficient info in the archives. Solder Balls probably hold the majority of posts and should be easy to referance. You can find out what causes them in relation to board material, profile tempature, wave type, flu
Electronics Forum | Mon Aug 07 16:23:34 EDT 2000 | Ramon I Garcia C
Hi!!! Thanks frieds for your advising, I have a MPM UP2000, I'm going to chek the humidity control, too I'll chek the profiles again, this plant it's located close to the beach about 1/2 mile from. However if you know some table to calculate t
