View Full Version : HSS Drill Blanks vs M-2 HSS Tool Bits

10-13-2012, 09:45 PM
What differences, if any, are there between HSS drill blanks and HSS round tool bit blanks?

I have yet to come across a material specification for an HSS drill blank. The data on
commonly available HSS tool bit blanks typically describe these as M-2 material.

For fabricating home shop tools for turning, boring & ect , does one serve any better
than the other?


10-13-2012, 11:45 PM

Just from my own experience, drill blanks are M2. Round lathe tools can be had with or without cobalt, M2 or better. I don't find much difference in practical use.


10-14-2012, 01:25 AM
M-2 is a pretty general grade, there are a lot of ways to improve that...just today I found drill blanks w cobalt (though no percentage was given) but not in a lot of size choice. For me there is little practical difference.
Right now MSC, round tool bits, you are looking at SECO (M-45 ?), Enco has M-2...sometimes its almost easier finding carbide rounds. If you really need them, and who doesn't, M42 drill blanks 36" long can be found.

10-14-2012, 03:44 PM
It always happens.

Before posting, each search for Drill Rod brought up entries that had no material mentioned.
After posting, every one mentioned M-2 and some M-42.

The neighborhood outlet of a metal supermarket chain is holding out O-1 rod as 'Drill Rod'
when what I am looking for is a round version of the square HSS blanks I have used in the

I'll check at other metal sources for lengths of round HSS. Industrial tool & hardware vendors
might be able to supply drill bit blanks - as long as these are M-2 HSS, they'll suit my purposes.
Otherwise, there are on-line sources such as those mentioned by RussZHC.

As for M-42 with its higher Cobalt content. As an HSMer, I don't 'need' the benefits offered by
the increased Cobalt so I'd just as soon stick with the basic grade and eliminate or minimize the
Cobalt dust arising from shaping & use.

BTW - my searches suggest that the Cobalt content of drill bits is announced by the HHS grade.
M-35 is said to have 5% Cobalt, M-42 to have 8%. (M-2 has none.) Inhalation of Cobalt fume
and dust is a bad thing.

Thank to all for the replies.


loose nut
10-14-2012, 04:35 PM
Something like this maybe.


10-14-2012, 10:18 PM

Oh I think we had a difference of terminology. In your original post you asked about drill blanks, which are generally M2 HSS. It seems you asked a local supplier about drill rod, which can commonly also refer to the simpler O-1, W-1, or even A2 tool steels. This may have led to some confusion between the two of you.