[bonz]

Hello,
I am new to this website (tonight). I hope I am not posting this thread in the wrong section...
Does anyone have experience in hard turning carbide? Not green carbide (before pressing), the really hard stuff... 75+ Rc... I have experience and success with nickel grades ie: CD-12N, but am having a bear of a time with micro grain carbides that do not contain Nickel.
We are trying to hold within .0002 in. over 2+ inches of profile work. Finish must be excellent (10 rms or better). At least there are no interrupted cuts (thank goodness). Currently using PCD tipped tools (DNMA-433) and trying various toolholder geometries. Roughing eats up PCD inserts (as expected) but must be done as preforms are not very close (having to remove .015 or so per side before even thinking about finishing).
Any suggestions and/or comments would be greatly appreciated.

Thanks for taking the time to read this,
Bonz

[HuFlungDung]

Golly, that's a real man's definition of "hard turning": hard turning carbide Its the first I've heard of it being done in a lathe type operation. Is it better than grinding for some reason?

[DareBee]

Hu
Turning probably is 10 times faster and to create the geomtry a lathe can produce a CNC grinder is 3-$500,000 easy.

Bonz do you know what brand and grade PCD you sre using?

[bonz]

DareBee,
Sorry to take so long to reply. Got real busy this last week. I will have to get the data on which grade of PCD is used. Using RTW Grade 3010 on CBN Tipped for hard turning steels (A-2, D-2, CPM-M4, Etc...). This works great. Even turning a part at Rc 60-62 with 17 interruptions - holding up much better than expected.
I will send more info soon...
Bonz

[runnoahrun]

Also, does anyone know if there are options besides EDM for drilling 1/2" holes into carbide, 3/8" deep?

[DareBee]

If they are thru holes you could waterjet.