Electronics Forum | Mon Jan 24 22:28:57 EST 2005 | davef
In addition to the potential problems you mentioned, add: * Barrel cracking of PTH and via. * Lifted pads. * Warped boards. And the reason you're not using a solder fountain to to solder this connector is? Or use an old trick we've done here on SMT
Electronics Forum | Tue Feb 24 09:52:14 EST 2004 | davef
First, two points about hole / barrel fill are: * A filled hole is an excellent indicator of the optimum process and optimum quality PCB. * The study that showed that holes need not be filled was paid for by the US Army and performed by Lockheed in
Electronics Forum | Thu Nov 17 20:23:55 EST 2005 | davef
We're with your customer. We believe inner layer separation is not linked to a heating excursion. What you are seeing is separation between the hole wall and the copper plating in the barrel of the hole on an unstressed PTH. Although, it's possibl
Electronics Forum | Tue Oct 27 06:29:49 EDT 2009 | lococost
Yes it is possible, and yes you shouldn't trust boards that have this problem. You're best off baking PCB's this old befor reflow. This looks like barrel cracking, a quick google gives: http://www.eco3.co.uk/e3toolkit/e3toolkit/modules/05/05_04_j_pc
Electronics Forum | Fri Jan 21 14:51:08 EST 2000 | Dave F
Mike: I�d hate to see you making design decisions, based solely on the discussion here, but that this would be an impetus to consult IPC-D-279, "Design Guidelines ... " and take a course on designing reliable boards. Werner Engelmaier (Engelmaier
Electronics Forum | Wed Sep 27 12:44:52 EDT 2000 | Ashok Dhawan
What could be possible resons for " Plating Crack on Barrel (tented via)" This tented via is in proximity to parts being hand soldered. The crack in barrel was detected on failure analysis - micro-section of via where barrel is having crack ( circul
Electronics Forum | Fri Jan 07 09:03:44 EST 2022 | jineshjpr
Hi Everyone, I want to understand what is the copper thickness to be maintained in PTH Barrel hole. Is this same as Fab recommendation of surface finished copper thickness like 25/35/70 microns..??? Is there any specific IPC standards available to un
Electronics Forum | Fri Oct 15 08:01:12 EDT 2010 | patrickbruneel
What you have is blowholes. Baking your boards prior to soldering will help. Root cause is either barrel plating too thin or barrel cracks allowing laminate moisture to escape. Patrick
Electronics Forum | Fri Oct 15 11:03:50 EDT 2010 | hegemon
Well, we got the baking part right at least. I would think that would help to rule out the barrel cracks allowing moisture escape. Plating too thin makes sense to me. In any case, do you think barrel cracking would be observable on a bare PCB?
Electronics Forum | Tue Oct 27 16:22:00 EDT 2009 | davef
It's not the first thing we think of in looking at your picture. First off, the lack of copper in the region of the red oval makes us think of a plating defect. We don't expect that moisture out-gassing through the barrel wall to show-up on opposite
