In a message dated 6/13/2004 12:13:09 PM Central Standard Time,
dg140@... writes:
While drilling Many small holes in PCBS--or any plastic or plexiglass for that
matter--it seems that the bit will become coated with plastics.
Charles: No. The material does NOT do this. Of course, the bits must be
clean and sharp at the outset, but a good sharp carbide bit will not accumulate
either copper nor glass-epoxy, perhaps partly as the two are not MISCIBLE.
You should find a "local PCB house" and get invited to come see their
Excellon (or whichever) CNC PCB-drill going at it! It will blow you away! And they
can show you their NEW bit-inventory and the USED-BUT-STILL-USEABLE
bit-inventory, and discuss with you whether they sharpen ("recondition") or just throw
OUT the used bits (Some GOOD houses do BOTH!).
If you watch for goodies, you MIGHT discover, as I did, that they TRASH
anything 4" and narrower. I got enough FR-4 between 4.25" and 3.8" to last ME for
a long, long time in my home-brew stuff, last time I visited the local
"house"! Of course, most of it is only ½-oz., but it's still good enough for
tinkering!
Jan Rowland
[Non-text portions of this message have been removed]