In a message dated 09/14/1999 4:12:11 PM Central Daylight Time,
[log in to unmask] writes:

<< Al -

 At a guess, I'd say there is a real good possibility that the tape adhesive
 will turn loose at this temperature and leave you with a mess on your hands,
 comprised of loose tape and parts.  You probably ought to try some samples
 first.  It would probably be a good idea to consult the parts manufacturer to
 lear the charactaristics of the molding compound used on that date code of
 parts.  They should be able to tell you the level of moisture susceptibility
 and preferred dehumidification routines.

 Regards - Kelly >>

Al,

One other thing to think about with reeled components is that the top cover
film adhesive used may be of the thermal cure type (which I think is used
quite a bit), in which case the peel force increases with temperature...you
may be REALLY sealing them in by baking the whole reel...

5-year old components huh? You might want to check with:

http://www.sixsigmaservices.com

I know they can bake the parts, re-tin them, and tape and reel them back up
for you. But I don't know how much that would cost. Just one other comment,
how big are these parts? If they're like SOIC-14's or 16's, I don't know if I
would be so worried about "popcorning" with smaller parts such as these...the
risk comes from the larger packages as far as I know. One thing you might do
in your reflow profile, is to keep your ramp-rate down below 2-degrees per
second, and definately don't exceed 220 C.
That'll be more gentle on the parts...but I've always been more worried about
QFP's and large PLCC's, rather than SOIC's...should I worry about those too?

-Steve Gregory-

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