Electronics Forum | Thu Sep 13 11:21:45 EDT 2001 | aldo_maldonado
We've had several instances of parts (1206R, SOT-23) popping off of their location during reflow. Parts placement is OK, paste brick is aligned and compact before oven. But we get random parts off their location just lying somewhere else on the boar
Electronics Forum | Thu Sep 13 13:34:49 EDT 2001 | Dave G
Too much Convection Airflow in the Reflow Oven blowing parts around ? Moisture Contaminated Parts out gassing ? Board out gassing? Just some thoughts, DG
Electronics Forum | Fri Sep 14 01:43:36 EDT 2001 | dhanashekar
please check the following also. in one of the cases we came across the second point was the problem. 1. the parallelisum of the conveyor. 2. the warpage of the board. 3. the stencil.(the differential height in the paste deposition of the two pads
Electronics Forum | Thu Sep 27 21:19:56 EDT 2001 | stimpy
>> try a linear ramp to allow the entire pcb to heat up evenly. What is your conveyor speed?
Electronics Forum | Fri Sep 28 09:30:07 EDT 2001 | kmorris
Just had a similar phenomenon 2 days ago. May relate to your issue --- or not. Like you, I did a once over looking for mechanical obstruction & couldn't find any. Ran a thermal profile on the offending PCB & all checked out. Looked in end of oven
Electronics Forum | Thu Sep 13 17:57:59 EDT 2001 | davef
You're correct. It is curious. Possible angles to look at are: 1 WS609 loves moisture in the air. In high humidity shops, this paste hakes-on liquid. If this is the case, you should also see slumping, resulting in fine pitch bridging, and solder
Electronics Forum | Thu Aug 13 16:25:11 EDT 2015 | emeto
Loctite 3609. Just a small dot under the D-Pak and it works 100%.
Electronics Forum | Tue Aug 11 09:48:22 EDT 2015 | samputrah
We have had two jobs that have the same issues with DPAK's sliding off their pads during reflow. We tried to resolve this by placing epoxy on the side of the component to create a "dam". However this is not repeatable enough to be a quality resolutio
Electronics Forum | Tue Aug 11 09:52:53 EDT 2015 | rgduval
I assume that these parts are falling off during second-side reflow? The easy solution, of course, is to not build high-mass components on first-side reflow. If this isn't practical, however, you can try using epoxy/glue under the component. We'
Electronics Forum | Thu Aug 13 14:10:01 EDT 2015 | markhoch
Hi Sam, I have a feeling that what you're trying to communicate is that your DPAK's are skewing off the pad during reflow. This is caused by a thermal "mismatch" where the solder paste on one side of the DPAK becomes molten before the other, then th
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