Jim,
I posted some experiences awhile back with carbolization of FR-4 around
the edges of holes in an FR-4 connector insulator that was laser cut. It
is conductive. Once the carbolization is present, high current leakage
can make it worse, until catastrophic failure occurs.
It is almost like CAF in that respect.
I'm sorry I do not know what they did to remove it after laser cutting. 
 

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Jim Henderson
Sent: Thursday, January 24, 2008 2:49 PM
To: [log in to unmask]
Subject: [TN] laser carbon residue

All,

 

We do quite a bit of laser cutting here that leaves a light carbon
residue on the edges of the board and holes.  Right now we are cleaning
it off with a cloth and alcohol at final inspection.  Is this common
practice or does anyone know a better way?  Our laser is UV powered if
that helps any.

 

Thanks in advance for any help.

 

Jim Henderson

Colonial Circuits, Inc.

800-578-9602 ext 118

 

 


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