Carrie,

We have also seen cracking caps after this type of depanelization. I just can't seem to grasp the forces during this process that would cause a capacitor to crack. Do you have any further insight into this?

Thanks,

Blair

>>> [log in to unmask] 08/28/03 09:54AM >>>
We have seen an increase in cracking.
The root cause for us is depanelizing using a rotary style blade cutter.
Caps and some filters too close to the edge are most subject to damage
due to the forces imparted on the board when depanelizing.  Often we
can eliminate the problem by flipping the board over during depanelize, but,
that does not always work and since we do not have the tools to analyze the
forces during the depanelize process, any changes like flipping the board
over is essentially a bit of a gamble.
 
-Carrie

-----Original Message-----
From: Bob Perkins [mailto:[log in to unmask]] 
Sent: Wednesday, August 27, 2003 7:42 PM
To: [log in to unmask] 
Subject: [TN] Cracking Ceramic SMT Capacitors


Cracking Ceramic SMT Capacitors
 
" Is anyone else seeing an increase in the number of cracked and shorting ceramic chip capacitors?  In our experience as a contract manufacturer we have, in the past, seen the occasional instance of ceramic capacitors cracking and shorting out. The cause of this problem is generally obvious, as it is isolated to components situated in areas of the PCB that are subject to flexing. 
 
Recently however we have seen more frequent instances of this problem; very often in areas of the board that should not be experiencing any appreciable flex. Our process has not changed and neither have our sources of these components. Have chip capacitors themselves become more fragile?" 
 
Rod Lafond
Manager, Quality Assurance and Technical Training 
APEX-Micro Manufacturing Corporation
[log in to unmask] 
 




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