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Received: by smtpgate.tcs.teradyne.com with SMTP;22 Aug 1995 09:29:29 -0500
Date: Tue, 22 Aug 95 09:30:16 0000
From: Lisa Greenleaf <[log in to unmask]>
Organization: Teradyne Connection Systems
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It has been our experience that nailheading is affected by copper type 
as well as drilling parameters and board stack up/design.  Feeds and 
speeds are most common, however a board design with heavy copper layers 
surrounding thinner foils tend to be prone to nailheading.  The dendrite 
activity is much more concentrated on HTE foil than on STD and although 
there is certainly differences in the physical properties of the two, 
many times what appears to be a nail head is really a dendrite.
Regards,
Lisa Greenleaf
Teradyne Circuits Operations
603-880-9461 x118
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