Thread: turning hardened steel

Originally Posted by tanii51

im trying to reduce the bottom thickness of a T nut to fit into the slot in the tool post slide(hercus) whilst it is machining its making hard work of it . i think its been hardend. im using tc tooling at slow speed the swarf is coming of almost red hot and some with sparks maybe im doing it wrong or shouldnt be done

GDay mate,
If you can get hold of a tungsten tip tool it would make the job a lot easier.
You will find that you will be able to increase spindle speed as well as your feed rate.
I use tip tools to turn HSS so you should'nt have a problem.
Regards Marc.

John
It will probably chip the TC insert if it is too hard.
Best to grind the underside away, as the surface accuracy for this part is not important.
Peter

HI tanii51,
I didn't think T Nuts were hardened, Perhaps some are. On My Mill Drill recently when I was Machining some Steel. I took a couple of nicks out of two of the Upper Nuts for the t Nut Studs. That was with Tc on a Face Mill (63mm Dia) did'nt worry it all. I recently Modified a R8 Taper Face / Shell Mill Arbor that was 27mm Dia on its Spigot to 7/8. It took me 1 Hour to do this (only a small Lathe). I could'nt find a R8 Taper Arbor with a 7/8 Spigot only ones in 22mm. I done this on My Bosses ML7 Myford at the Fastest Speed only has 3 Pulley Steps (don't know RPM). I used Tc that is for Hard Material. I bought both the Lathe Turning Tool and the Tc of Minitech. I was told (I thought so too) that the Arbor would only be Case Hardened. Well the Arbor ended up being Hardened as it was'nt till the last MM and turning the Tip around that it Free Machined. It Chattered a lot during the Process . I did Grind a Bit of the Dia. off but definitly no more than a MM.
Why do You need to reduce the thickness anyway?. Have You thought about Grinding them. With Tc You generaly Machine at a reasonable Speed. My advice is get some Tc tips for Hard Material and step up the Speed a bit. Happy Machining.
All the Best steran50 Stewart