Electronics Forum | Wed Jun 10 22:47:17 EDT 2009 | davef
You're correct that JEDEC J-STD-033 defines baking condidtions for moisture sensitive components. Why do you want to bake assemblies after cleaning? Search the fine SMTnet Archives for threads like: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Me
Electronics Forum | Wed Jun 24 05:08:37 EDT 2009 | Mark
Try immersing the assembly in IPA for 30 minutes. IPA is hydroscopic ans will drive off most of the water. Dry the assembly. Then bake at 110°C for 2 hours.
Electronics Forum | Thu Jun 11 22:57:45 EDT 2009 | davef
NASA recommends baking a PCB for a minimum of 4 hours at 93+/- 5.5�C before conformally coating. [NASA-STD-8739.1, �Workmanship Standard for Staking and Conformal Coating of Printed Wiring Boards and Electronic Assemblies,� August 6, 1999]
Electronics Forum | Tue Jun 09 18:44:20 EDT 2009 | dyoungquist
We are using a water soluble flux which requires the assemblies to be cleaned in an ultra sonic cleaner after assembly. Is there a standard that specifies how long the assemblies need to be baked/dried after being submersed in a water solution for a
Electronics Forum | Fri Jun 26 00:28:43 EDT 2009 | Mark
IPA is hydroscopic.
Electronics Forum | Tue Jun 30 13:20:10 EDT 2009 | charliedci
He wants to "see underwater"
Electronics Forum | Thu Jun 11 10:02:36 EDT 2009 | dyoungquist
Our cleaning process involves the assemblies being completely immersed in the water bath of the ultrasonic cleaner. The assembly has a QFP44 on it. Customer stated that when these assemblies have been cleaned with water in the past (at a different
Electronics Forum | Thu Jun 25 20:01:54 EDT 2009 | davef
Shanelo Technologies Given that isopropyl alcohol [IPA] is produced by combining water and propene. How does soaking a board in water and a flammable liquid drive off water?
Electronics Forum | Wed Jul 01 05:26:31 EDT 2009 | kpm135
But the boards and parts on the boards are also hygroscopic(no not a typo I did a search on hydroscopic and it is not a word the actual word is hygroscopic look it up if you don't believe me) so if you have two hygroscopic materials which one wins?
Electronics Forum | Thu Jul 14 01:43:09 EDT 2005 | pyramus
Solder paste used was Kester FL250M (no-clean).... components affected were only chip components 0603, no BGA & no IC components.
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