Rick,

I do not know what flux you are using but wouldn't you start to drive off
any volatiles in the flux.............

joe

-----Original Message-----
From: Rick Thompson [mailto:[log in to unmask]]
Sent: Thursday, July 01, 2004 8:54 PM
To: [log in to unmask]
Subject: [TN] Long Reflow Soak Times for BGAs?


I'm having a philisophical discussion with my boss regarding long reflow
soak times to improve soldering under BGA devices.  Is there anything to be
gained by extending soak times at the 150C level from 60-90 seconds to 5-10
minutes? I've never seen times this extended and am wondering if they make
sense in some situations?  The boards in question are not terribly
difficult, .063" thick, 14 layer, 12x16 inches with maybe a couple thousand
components on top.  Any comments on this practice?

Thanks in advance,

Rick Thompson

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