On Sep 25, 12:19*pm, Ignoramus10035 ignoramus10...@NOSPAM.
10035.invalid wrote:
eBay is full of those:

* * *http://shop.ebay.com/?_nkw=%22micro+drill%22+carbide

or similar tiny carbide end mills.

My question is how usable are they on a hobby sized CNC machine like
my Bridgeport Interact, with slow top speed. Is using them totally out
of question, or just frustrating, or perhaps they are handly for small
work?

i

Well, they are used on machines not much different from hobby machines
in both size, but speed is way higher. However, there are both drills
and "burrs" in the machines. Obviously the drills do holes, only! The
burrs are used to mill the outline of the circuit board so as to
completely cut it from a panel of boards, or sometimes just leave
small tabs between boards in a panel. In other cases, a special "V"
shaped burr is used to mill a scoring line between boards so they can
be cut apart after populating them with components.

I have several assorted sets from both Grizzly and from Ebay. All are
1/8" shank. When we have to drill or mill a board, we use a variable
speed drill press, 0-20,000 or 0-39,000 rpm.

Paul