Hi TechNet -
     
     You have me confused about what type of component(s) you are dealing 
     with (a "component block" is a term I am not familiar with) but the 
     source of your solderability is pretty straight forward. Cardboard is 
     notorious for outgassing many different contaminates that can 
     interfere with solderability. Silver finishes can tarnish in hours due 
     to sulfur contamination from cardboard. What is the component finish 
     and are you controlling the type/quality of cardboard the components 
     are stored in? Also what is the storage environment conditions 
     (temperature, humidity, etc.).
     
     
     Dave Hillman
     Rockwell Collins
     [log in to unmask]


______________________________ Reply Separator _________________________________
Subject: Solderability of component blocks
Author:  [log in to unmask] at ccmgw1
Date:    4/9/97 4:01 PM


We have notice a problem with solderablity of component blocks after 
they have been sitting for a while in cardboard for a while.  This has 
created blow holes in the solder joint, the problem has gone away after 
cleaning the parts with alcohol.  Has any one else had this problem, and 
what kind of packing material will not produce this problem?
     
*************************************************************************** 
* TechNet mail list is provided as a service by IPC using SmartList v3.05 * 
*************************************************************************** 
* To subscribe/unsubscribe send a message <to: [log in to unmask]>   * 
* with <subject: subscribe/unsubscribe> and no text in the body.          * 
*************************************************************************** 
* If you are having a problem with the IPC TechNet forum please contact   * 
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask]      * 
***************************************************************************
     

***************************************************************************
* TechNet mail list is provided as a service by IPC using SmartList v3.05 *
***************************************************************************
* To subscribe/unsubscribe send a message <to: [log in to unmask]>   *
* with <subject: subscribe/unsubscribe> and no text in the body.          *
***************************************************************************
* If you are having a problem with the IPC TechNet forum please contact   *
* Dmitriy Sklyar at 847-509-9700 ext. 311 or email at [log in to unmask]      *
***************************************************************************