Electronics Forum | Mon Aug 01 06:59:02 EDT 2005 | Joseph
Dear all, We observed visible micro crack at top side of solder fillet during lead free wave solder process. We did not see any visible micro crack at bottom side, and it always located at joints of transformer. Any input be much appreciated. Best
Electronics Forum | Thu Jul 18 04:42:32 EDT 2013 | ericrr
Thanks for that, sorry Im late setting (set by someone else) Speedline Bravo Top 1st chamber, 2nd, 3rd, 4th. 170° (c), 180°, 190°, 270°. Bottom 170°, 180°, 180°, 260° chain speed 27cm/second.
Electronics Forum | Sat Nov 09 15:13:06 EST 2002 | mjabure
If I understand what you're saying, you are reaching reflow temp's on the top side while soldering bottom side components. You might want to run a glass gauge plate over the wave and make sure your contact pattern isn't too large. If your PCB is in c
Electronics Forum | Tue Nov 13 12:25:12 EST 2007 | gradloff
I have a thick board with ground planes that will be soldered by hand with a mildly active solder/flux. X-ray confirmed that solder was added to the top of the joint causing a void between the bottom and top solder joint. Other than the mildly acti
Electronics Forum | Mon Aug 01 20:02:20 EDT 2005 | Joseph
We use SAC305 and top side particular joint temp. is 110 deg C, and the terminal finish for that particular lead is pure tin. It look like hot tearing at the primary side of PTH.
Electronics Forum | Tue Jan 21 13:51:19 EST 2014 | rgduval
Armando, Is the problem in the same spot on the board with every run? If so, there might be something about that particular location that is part of the cause (ie. ground or power plane connection). It sounds like you're seeing blow holes, or insu
Electronics Forum | Thu Aug 29 20:00:32 EDT 2002 | iceman
Steve, I agree, you should expect to have better results from double sided reflow. It is more difficult to dial in a wave solder process for SMT components than a reflow oven. Besides that - adhesive is just no fun to work with.
Electronics Forum | Thu Aug 29 20:04:13 EDT 2002 | davef
Steve: I agree. Let�s break it down. * I�d rather print paste than glue any day of the week * But I know yera �Dispenser Boy�. In that case, I�d rather dispense glue than paste. * PTH / primary and SMT / secondary is a tough process either way you
Electronics Forum | Mon Oct 29 18:21:43 EST 2001 | slthomas
We recently have received a lot of warped (bowed and/or twisted behond IPC 600 specs.) bare boards (some our fabricator's fault, some ours by design) and I can't help but figure that long term reliability will suffer when building product with them.
Electronics Forum | Tue Oct 30 10:54:37 EST 2001 | slthomas
Hey, Preacher, choir here. Unfortunately I didn't get to make the call here (hot boards, new product, same ol' same ol'), but I dam* well am looking for future (print) backup to assist in persuading the bottom line guys that it's cheaper to wait for
