Tantung G cutting tools.

[Gary S]

Has anyone had any experience with using this material ?.
I bought a couple of pieces to give it a try and am just waiting for it to arrive in the post.
It's composed mainly of cobalt, chrome, tungsten, and a few other metals including a little bit of iron. From the information I have read it retains its temper up to 1500F, is harder than CoHSS, and retains its edge better on tough materials.
ASTEG - Tantung Cutting Tools (http://www.asteg.com/07metalcut/TantungCuttingTools.htm)

[matthew_g]

Interesting read Gary,
I suppose the only way to find out is to try. If it as good as it's represented the only limiting factor would be cost effectiveness

[Gary S]

Well the Tantung arrived and I was pretty impressed with the results on 304 stainless.
Ran the lathe at 1500rpm with a 2mm depth of cut, and fed it in at the fastest feed rate the lathe would do, did several runs of about 50mm length and it worked really well.
I tried the same thing with a piece of M42 HSS as a test and it wrecked the point and edge within 5mm.
I did a cut of 3mm when the diameter got down a bit, on the bigger diameter it was slowing the lathe down :D. I changed the inverter a while ago and it's lost a lot of grunt :((
I took a bit of video so if you want to have a look it's here. (edit) Cool, didn't realize the video would be embedded on the forum.
Diamond Tool Holder turning 304 Stainless - YouTube

[Bryan]

Sounds like it's kind of in between carbide and HSS. I wonder what's the best way to grind it? They don't mention that on the page you linked. Thanks for the report Gary. Keep us posted as you get to know it better? BTW what was the cost?

[Gary S]

Hey Brian. It comes in 6" lengths and costs $99 a length for 1/4" square, a bit more costly than M42 HSS, but a 10 pack of decent carbide bits would cost at least that and I'm sure wouldn't last as long. Grinding is done on a normal wheel, I just sharpened it on my grey wheel that came with the grinder years ago. Have to try it on a few more materials yet, will be interesting to see how it goes on cast iron and tougher types of stainless.