Neal,

We did experience incompatibility with a very common OSP product and aramid 
random fiber.  The six hour back suggested by the laminate and pwb suppliers 
exceeded the protection abilities of the OSP.  We now define our aramid 
random fiber pwbs with electroless nickel - immersion gold and have had no 
problems hence.

Kevin Thorson
Lockheed Martin
 ----------
From: TechNet-request
To: TechNet
Cc: njpreimesberger
Subject: Re: Assembly:  OSP and Bake.
Date: Wednesday, June 19, 1996 3:31PM

     Hello Neal - OSPs are not OSPs! There are several products available
     on the market and they all have various degrees of thermal excursion
     durability. The type of reflow environment (nitrogen or not) and
     cleaning system (for say a double pass assembly that gets cleaned
     between reflow passes) are factors to consider too. Send an email on
     which specific OSP you are using and we can discuss.


     Dave Hillman
     Rockwell Collins
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______________________________ Reply Separator
_________________________________
Subject: Assembly:  OSP and Bake.
Author:  [log in to unmask] at ccmgw1
Date:    6/18/96 7:15 PM



     Anyone pre-baking prior to the wave with OSP on the boards.  Time and
     Temp?  Seems I heard about an oxidation of the Cu under the OSP, or
     was the T & T too much?  Question comes up because of the necessity to
     bake things such as Thermount boards prior to any temp. stressing.

     Thanks, Neal Preimesberger, HMSC Tucson.  520-794-1030
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