Electronics Forum | Wed Aug 11 06:27:07 EDT 2021 | danisa
Hi all, The PCBA was swollen after SMD It is hard PCBA with 6 layers and SMD both sides Defect rate: ~ 5% Phenomenon: swell at the same side, same position (at 2 IC positions). Did not find any abnormality in SMD process as well as storage condition.
Electronics Forum | Thu Jan 15 15:08:43 EST 2004 | mrmaint
Are your qfp's being stored properly. I have seen this in the past and it turned out to be a moisture issue. We saw most of the problems on the corners. The component would swell during the reflow process thus lifting the corners. After baking the re
Electronics Forum | Fri Oct 23 17:33:42 EDT 2009 | grizzy
Check that you are following the moisture sensitivity requirements for the part. I've seen the part swell underneath. You can contact me at wenroth@reconsales.com for more information. I am an 'ol reflow guy from the CM world. Wes
Electronics Forum | Fri May 21 09:48:30 EDT 2010 | tomg_fla
Am looking for a dispensable water soluble solder mask or peelable solder mask that can be dispensed and be run through a reflow oven with no swelling or degradation. Any leads on any materials or manufacturers to contact?
Electronics Forum | Mon May 24 12:05:53 EDT 2010 | deanm
Did you try Techspray Wondermask W? It is water soluble and can probably be transferred from the bottle to an EFD type syringe for dispensing (we use the P and the PL that way). As far as if it will swell through the reflow, I don't know. We don't us
Electronics Forum | Sun Jun 29 07:31:03 EDT 2014 | vitrost
Hi, We had experienced very similar issue on boards of a certain PCB manufacturer. Field experiments showed that the solder mask of this manufacturer is prone to swelling and peeling after it was in contact with our water-based flux. When you switc
Electronics Forum | Thu Feb 07 12:04:11 EST 2019 | davef
Over the years, Bob has contributed many videos and pictures that have help identify and solve production issues. I recall a vid of a bug-up BGA being heated to liquious that showed the balls swelling in the heat to the level that they bridged. Bril
Electronics Forum | Tue May 02 17:26:33 EDT 2000 | Steve Thomas
As I understand it, though, a 90 sec. 75F wash and a 15 second rinse (plus the lift cycle, another 10 secs., perhaps) at a MAX. of 110F isn't supposed to be nearly enough of a swing to swell that epoxy or expand the foil. According to my contacts at
Electronics Forum | Wed Nov 10 16:19:51 EST 2010 | davef
The 5 thou standoff of your SOIC is probably the minimum. We wouldn't be surprised to see 10 thou. With this, you could have maybe a 6 thou gap between printed solder paste and the bottom of the heat slug. So, you're expecting the rabbit ears of p
Electronics Forum | Thu May 24 08:40:18 EDT 2001 | toolman
hi kris well 0.02 cents south african money is a lot less. but anyway we have a customer with 3 lines all lines are the same equipment and we have had major problems with 0402s .on some manf reels .as a test we moved one reel around and the problem m
