Remember the carbide is C-2 on a lot of stuff up to c-4. C-6 is on the machines.

Martin H. Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
"Our Republic and the Press will Rise or Fall Together": Joseph Pulitzer
TSRA: Endowed; NRA LOH & Patron Member, Golden Eagle, Patriot's Medal.
NRA Second Amendment Task Force Charter Charter Founder
IHMSA and NRA Metallic Silhouette maker & member. http://lufkinced.com/

On 6/23/2010 4:31 AM, N_Cook wrote:
Thanks all. AFAIAA the tips of masonry drill bits are always carbide. Tried
an unused part of a needle file against such a piece of carbide and a known
HSS drill bit and could not convince myself either way. Don't know what sort
of grit, but rust brown (binder?) parting off disc in a Dremmel. Just
cleaned up the surface of the carbide and slotted the HSS.
So repeating with these unknown small bits , HSS