Apart from all thinks suggested (humidity ; large copper grounds, etc.) ;
what gave us the worst on this line was undercured (UV) LIQUID PHOTO .
Apparently speeding the process or underpowered lamps can leave top dry and
on copper contact not so .
Than reflow measled it all . No idea if baking does influence this scenario
(never bothered) :
Did as Bev did afterwards . Not that you would have this luxurious options ,
as I remember when I've had a sub shop ; you take what you get, say yes sir
and do (not look) your best.
This Nortel fellows bake on sunshine comforts forgetting mere mortals
sometimes .

Paul Klasek 
ResMed

-----Original Message-----
From: Stephen R. Gregory [mailto:[log in to unmask]]
Sent: Tuesday, 31 August 1999 6:37
To: [log in to unmask]
Subject: [TN] Delamination and Blisters after Wave, a follow-up...


Hi ya'll!

Well, I waved a dozen more of the boards that blistered on me Saturday. This

time I "baby-sat" the boards from baking to wave. I baked them at 125º C.
for 
3-hours, and waved them within 2-hours after baking...no blisters this time.

They were the same datecode as the ones that blistered on Saturday (9915)
and 
even a few of them had a 9831 datecode...but nada blisters. I used the exact

same profile I used Saturday when I waved em' too...

Hmmmmmm...

I've got a digital camera and if anyone wants to see the blisters I got on 
Saturday, I can send ya' a picture.

From the responses I got from a number of people and from a lot of the 
messages I read in the archives on this subject, if I were a betting man, I 
woulda bet that the boards would have blistered on me today...but they 
didn't...

-Steve "Guess I'll bake more often now..." Gregory-

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