Electronics Forum | Wed Jun 18 11:34:23 EDT 2008 | slthomas
"And we have evaluated this process before 2001." How did you quantify the level of moisture left in the components after the bake?
Electronics Forum | Thu Jun 19 07:41:25 EDT 2008 | davef
And that's the key thing for an assembler. Who cares if the part is bone dry? Assemblers want to get the part dry enough so that soldering process does not destroy the part, so that he /she can move on to the next issue.
Electronics Forum | Wed Jun 25 22:18:53 EDT 2008 | fowlerchang
Sorry! I can't insert the document. So give me email if you want to receive this evaluation report. fowlerchang@rayval.com
Electronics Forum | Thu Jun 10 04:52:36 EDT 1999 | Gyver
Hello all! Recently we got a problem about the Funtional test. Some boards passed tests by using the auto-fixture(vacuum), but failed by using manual test fixture(need to plug CPU, DIMM etc.). The error symptom is no picture. We doubt it's the proble
Electronics Forum | Wed Dec 19 15:12:25 EST 2007 | slthomas
I see. You might request that those parts be provided in the proper trays (125�) for starters, but I do understand the issues with contract assembly. I'd be inclined to write a program to pick them from that tray and place them into a proper one. Wh
Electronics Forum | Thu Dec 27 13:37:15 EST 2007 | chef
Mr. Wizard- Bingo, you did it again - don't know why I had to wait for the 3DBB before I saw the light. I have similar sitiaction to Steve - shake and bake, baby - two turns of the rotisserie- now ya got 2 bottles of californy spill on reserve - di
Electronics Forum | Tue Jun 17 15:35:12 EDT 2008 | slthomas
But don't you need to control the rate of the drop in pressure? I'd think if you pull down quickly it just results in the same popcorning you'd see in a reflow oven. I just know it's not hard to boil water in a vacuum chamber. For that matter, it's
Electronics Forum | Wed Jun 18 07:58:23 EDT 2008 | davef
Hi Stu Some seem to believe that vacuum baking will suck moisture from components and boards. Actually, the case is just the opposite. * Without proper definition and control of process parameters, vacuum baking retards the removal of moisture * Eve
Electronics Forum | Wed Jun 18 11:33:21 EDT 2008 | slthomas
Dave, can I assume that in the case(s) you're referring to, there was no gas introduced into the evacuation chamber to push any expelled moisture out of the system? In the industry I was involved with (implantable medical devices), we used nitrogen
Electronics Forum | Wed Jun 18 13:08:52 EDT 2008 | sleech
Dave: You are spot-on right! The major hurdle is that 70 degrees C is below the boiling temperature of water. Only a near zero relative hudity chamber will cause the ingested moisture to migrate from a package. There is one facet of the 70 degree p
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