Remembering from a prior life, we used to do 5 solder shocks, standard 
 Mil-P-55110C (the revision in force at the time) sample conditioning and 
 preparation.  The solder shock was a float at 550 deg.F. for 10 seconds. 
 Product used was random selection from what was being manufactured on the 
 floor at the time.  This regimen was used as a process control and was done 
 daily.  If the process did not pass 3 or more solder shocks, we would react 
 and go start looking at the contributing process variables (i.e. copper bath 
 condition, laminates used, Z-Axis, ductility, elongation, baking processes 
 etc.).  The actual product reject criteria, however, still remained that the 
 product had to pass 1 solder shock, as in the military specification 
 pertaining at the time.
 
 Hope this helps.
 
 Greg Schroeder
 [log in to unmask]


______________________________ Reply Separator _________________________________
Subject: In-process Test coupons
Author:  [log in to unmask] at SMTPLINK-HADCO
Date:    5/8/96 8:36 PM


Does anybody pull coupons immediately after pattern plate and solder float 
the coupons as an inprocess check?  If so how many floats and at what 
temperature: the usual 550F?  If mutiple floats are used what reject 
criteria is used?