Electronics Forum | Wed Jan 12 10:05:20 EST 2005 | Dreamsniper
we are using polyimide boards 6 inches x 7 inches, 2.5mm thick, 12 to 14 layers, for aerospace industries. I am using a long bake of 12 hours at 70'C prior to manufacturing or exposure to elevated reflow and wave soldering temperature. If schedule i
Electronics Forum | Tue Aug 14 15:45:06 EDT 2001 | davef
BOARD BAKING SCHEDULE: Bake time depends on the board thickness and construction. For laminated FR4 PCB, we bake between 6 and 24 hours at 100�C. ROOT CAUSE OF THE PROBLEM: Heating moisture entrapped between the laminations of the board too quickl
Electronics Forum | Tue Mar 17 10:47:56 EDT 2020 | davef
IPC-1601 covers PWB bake-out, methods for determining optimum bake time and temperature, caveats for certain PWB plating finishes, etc. IPC-1601 is to bare boards as J-STD-033 is to components
Electronics Forum | Fri Feb 10 13:30:31 EST 2023 | rwyman
Yes, that point remains unchanged. Just a general comment that there have been updates. e.g. re: desiccant re-use, certain devices no longer requiring bake-out, or bake times have been adjusted, and more.
Electronics Forum | Mon Nov 27 17:39:37 EST 2000 | Dave F
Daniel: In response to your questions: * Moisture level (wt%) that may cause delamination in PCB�s. - Certainly, it depends, but 100% moisture will not cause delamination of a PCB. [Now, heating that water is another question, isn�t it? ;-)] *
Electronics Forum | Fri Apr 15 14:43:52 EDT 2022 | djenkins62
Wanted to ask the SMT community if anyone has data on baking Clariant Desi Pak for 16 hours at 245 F. How are you cooling to avoid condensation reforming? Have you measured efficacy of desiccant after baked 10 times? 100 times 1000 times? 5000 t
Electronics Forum | Mon May 13 20:40:07 EDT 2002 | davef
Fine pitch parts are not the issue. Platic parts that absorb moisture are the issue. Search the fine SMTnet Archives to get started. Try: * MSD * Moisture sentive device * Dessicant cabinets * Baking times * 033 * 020 * etc
Electronics Forum | Mon Jul 29 16:52:51 EDT 2019 | stephendo
https://www.jedec.org/document_search?search_api_views_fulltext=j-std-033 You will have to register to download. It has the bake time charts. For BGAs at 40C we are talking days to weeks to months depending on thickness.
Electronics Forum | Wed Jan 05 17:53:52 EST 2005 | SuePH
We had a contract in house that included a flex board which required an 18 hour bake at 105 degrees. The other brds got along fine with 2 hours, but the flex board would delaminate until we went to this long bake. I don't know how the engineer came
Electronics Forum | Fri Feb 28 08:57:34 EST 2003 | davef
We used to bake [100*C for 6 hours] all of our boards, but no longer bake at all. Before going off, your bake recipe is probaly OK. If anything, it's probably too short. Consider measuring the weight of wet boards, baking for a time, measure, bake
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