Electronics Forum | Mon Jul 02 16:19:02 EDT 2012 | jorge_quijano
Thanks for you inputs guys. We left our customer know about the design issues, they will add fids on the next version, I hope it helps. meanwhile we'll deal with those issues. I tested a new stencil today and It has a better alignment than the older
Electronics Forum | Mon Feb 03 23:49:00 EST 2003 | Dreamsniper
Hi, Has anyone who's using vapor phase process able to help me troubleshoot tombstoning? I raed about uneven forces during reflow due to misalignment, pad design, paste volume deposition unevenness due to dirty stencils, worn stencil printer parts s
Electronics Forum | Mon May 06 12:44:50 EDT 2002 | Bob Willis
The SMART Group is starting a new project on PPM Monitoring which will be providing average PPM yield data per month free to the industry. I would like to get feedback or exchange criteria for paste printing as non exists with in IPC or similar organ
Electronics Forum | Mon Dec 13 05:43:27 EST 1999 | Wolfgang Busko
Hi Steve, 20 mil pitch shouldn�t be that problem nowadays. In your case bridging and poor wetting seem to go hand in hand. For the poor wetting try to eliminate it by using different paste (higher activated) and work on your profile. Coplanarity also
Electronics Forum | Fri Aug 09 03:59:35 EDT 2019 | sssamw
Did you check the pin location accuracy before placement? I mean if possible pin was hit or misaligned a little before placement, so the pin cannot inserted in hole then bent. And maybe you need contact your component supplier to study together.
Electronics Forum | Mon Apr 25 17:15:45 EDT 2022 | SMTA-64387687
It's difficult to diagnose without the LED specs. Is the spacing between the pads the same? Your pads seem too large for the Nichia part. Try reducing the stencil apertures to deposit less paste and closer to the inside edge. Depending on your oven,
Electronics Forum | Sun Sep 25 20:20:22 EDT 2011 | johnyq
We recently aquired an old MPM-AP25 stencil printer that printed paste with a large error (about .060 inches). I concluded camera alignment to be the cause but was surprised by the magnitude. I found the camera beam splitter prism misaligned and loos
Electronics Forum | Fri Nov 30 23:28:54 EST 2007 | mika
BTW, Option 6. Bear in mind though, In the stencil printer if you run into a problem like this, it will not work with the holes...Only what's in the stencil... We have under some rare circumstances used 1-2 pad's on opposite corners and on very large
Electronics Forum | Thu Dec 27 14:46:32 EST 2018 | emeto
Hi Prem, it will really help if you provide more pictures and metrics. Pad layout, part datasheet, stencil design and most of all picture of the misplaced part on the board. This looks like a very interesting case and I am willing to help you, but t
Electronics Forum | Mon Sep 13 07:27:50 EDT 2021 | denism
There may also be a problem with the a thermoprofile. Measure the temperature of both contacts of the component, if they heat up not evenly and the soldered lead heats up faster, then the problem is in the profile. To solve the problem of misalignmen
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