Electronics Forum | Thu Apr 25 09:34:24 EDT 2002 | fmonette
Michael, By the way, the default bake duration should be 48 hours at 125C instead of 24 hours. The shorter duration was based on a standard that is now obsolete. The current revision of J-STD-033 includes a variable duration bake table, based on co
Electronics Forum | Mon Oct 14 18:27:38 EDT 2002 | kennyg
In regards to baking an assembly prior to hot air (BGA) rework.... 1) Do people always bake, sometimes or never? Does this depend on whether MS sensitive components are near the rework site? If a BGA is to be removed and reballed, baking is a no-br
Electronics Forum | Thu Feb 07 09:07:10 EST 2002 | fmonette
Dason, Please be aware that weight gain is only a very crude estimate of the component moisture content. This is only accurate when the moisture is uniformly distributed inside the component (which is actually never). This measurement is usually no
Electronics Forum | Tue Oct 15 10:12:44 EDT 2002 | davef
1) Do people always bake, sometimes or never? Does this depend on whether MS sensitive components are near the rework site? If a BGA is to be removed and reballed, baking is a no-brainer. Sometimes, based on the proximity of the MS components. >2)
Electronics Forum | Sat Oct 28 02:25:19 EDT 2006 | mika
Agree!! Where is Your thermocouple-probes attacded and can we get the info from this? Delta-T of the comp. is very, very important! The single most important smt-process step is the profiling/recipy and as a result of this, this poor package will cor
Electronics Forum | Tue Apr 09 21:40:26 EDT 2002 | ianchan
We are a local enterprise with limited resources, just like you described, so hope this experience sharing helps : we place a production Visual Mechanical Inspection (VMI) inspector at the end of each Reflow Oven area, complete with magnify scope 30
Electronics Forum | Wed Mar 02 13:15:16 EST 2022 | chris007
I am currently working on a manufacturing flow where some PCBA are processed with reflow oven (after being baked before processing), then cleaned with bath, then passed into contaminometer, passed into AOI. The point is after all of this, if AOI dete
Electronics Forum | Thu Mar 03 14:01:16 EST 2022 | chris007
Hello Baking before solder pasting and reflow actually due to poential moisture development. This is JDEC requirement I believe to do so. We AOI after cleaning so we AOI a clean PCBA
Electronics Forum | Fri Mar 04 11:48:24 EST 2022 | dontfeedphils
Is there a reason the PCBA needs to be cleaned to inspect through AOI? I AOI thousands of "dirty" boards a day without an issue.
Electronics Forum | Mon Oct 14 17:59:45 EDT 2002 | russ
When I used the micro-stencils, We purchased the holder from the stencil manufacturer. As far as design we used 5mil stencils for uBGAs,6-7 mil for larger 63/37 balls, and 8 mil for CBGAs. Aperture openings used were slightly smaller than what we wo
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