Wow, how long an answer do you want?  saw Steve' reply and agree that
"poor wetting" is sometimes a perception rather than reality. In
addition to what Steve described I have had several other "poor wetting"
issues that took considerable explanation to quality. A tapered lead
that has a large shoulder may have solder suddenly stop because of the
rapid heat dissipation at the larger area. This was being rejected
untill I could finally convince QA. of what was happening. Give us some
more info and I am sure you will get several relevant replies.
Charles Caswell
Process Lead, PCB
Frontier Electronic Systems

-----Original Message-----
From: TechNet E-Mail Forum. [mailto:[log in to unmask]]
Sent: Friday, October 05, 2001 8:59 AM
To: [log in to unmask]
Subject: [TN] Poor wetting on solder joints 


What could be the cause of poor wetting on solder joints and how we can
solve it?

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