In a message dated 10/07/1999 7:46:54 PM Central Daylight Time,
[log in to unmask] writes:

<< TechNet,

 I need to tap a little expertise from the assemblers out there....

 I have a PWA kit to be built that has been sitting around for about 12-14
 months.
 No environmental storage of any kind, just in tubes and boxes in the
stockroom.
 What dilemma's am I likely to encounter with these components, if any??  I
 suspect
 the boards will need to be baked, but normal duration or more based on length
 of time on the shelf?? Any worry about warp and coplanarity?
 Any issues with components that have not been stored
 with any dissicant or anti moisture protection?  Any worry about lead
oxidation
 that requires cleaning/tinning for solderability/wetting concerns?

 Just wondering what kind of interesting things to expect or try and avoid,
 if any.

 Any suggestions or comments greatly appreciated.

 Tks......DT >>

Hi Darrel!

I don't know if this will help you or not, but about 3-weeks ago, I got the
pleasure of wave soldering some boards (about 2-dozen) that had been
partially assembled and had been sitting in tilt-racks for close to
10-months! There was SMT on top, some PTH, and also had components epoxied on
the bottomside (passives and actives) as well!

Don't ask me why they sat around that long...something about the project
being put on hold or something, I don't know. All I know is they brought the
boards to me and asked me to wave them. They asked before I waved, how did I
think they were going to do...I said probably like a pile o' poop, but I
didn't have anything to lose so I'd give er' a go. I baked them and then
waved them...used a OA flux. I musta' had the soldering gods looking over me,
they actually looked good! One of the supervisors came to look at the boards
while I was waving them to get ready for all the touch-up they were going to
do, but was amazed that they soldered as well as they did (I was pretty
shocked myself, but I didn't show it...kinda' smug actually)

Don't know if you'll be as lucky as I was...

-Steve Gregory-

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