Our companys design policy is not to put via sites in chip part pads. The "B" 
stage will leak onto the surface pads during the lamination cycle. This could be
the cause of the problem you are experiencing.

______________________________ Forward Header __________________________________
Subject: VIAS IN 0805 PADS WAVESOLDERING
Author:  [log in to unmask] at SMTPpost
Date:    4/16/97 8:23 AM


Hi,
Like everybody (?) we are using 0805 components in wavesoldering. 
When there is a viahole in the pad, we see a number of very thin 
solderjoints (almost undetectable visually) and even non-soldered 
components.
Is there an experience in the field about allowing or not allowing this 
configuration, and about via-hole size and via-position in the pad to 
reduce or prevent defects ?
Eddie Van Horen  [log in to unmask]
     
     
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From: VAN HOREN EDUARD VM81 014 57 20 08 <[log in to unmask]>
Subject: VIAS IN 0805 PADS WAVESOLDERING
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