drilling high speed steel

[Bob Hampton]

ok got a question
I have several old turning tools that are about done as far as to use on the lathe ..wore out...so wanted to make some cutting tips out of the scrapers for hollowing tools i am making....
Now I have no problem cutting them for size for the tip of a shaft ..but when it come to drilling them for mounting on a shaft ...as i can see...conventional drill bits are not going to work ..so what type bits do i need to drill this stuff with?

Thanks
Bob:D

[Mike Vickery]

I have never used it but this question recently cam eup on a different forum and this is what one guy claimed worked good.
Carbide-Tipped Straight-Flute Drill Bits
http://www.mcmaster.com/nav/enter.asp?pagenum=2405

I tried it once useing crabine tipped masonary bits and it was working but very slowly, but I rushed and screwed it up.

[Bob Hampton]

ok mike thanks for the info...think i will give the masonary bit a try as i have quite a few of those...the others are a little to spendy for me.

thanks
Bob

[David Epperson]

Bob
The masonry bits will work, but they will work better witha metal cutting grind on the tips. They come ground to cut, well, bricks and concrete, not steel. Grinding carbide takes a bit longer than grinding steel since it is quite a bit harder. And grinding drill bit points can be an art form into itself. But the basic peinciples still apply. Start small, pilot drill if need be, and grind as small and sharp a point on the carbide tip as you can manage.