I run a similar type part. At that Hardness. I agree with Tim, Helix bore out through the first .200. My feeds and speeds on the drilling cycle itself are 250SFM (947RPM) with .0075 feed. So its roughly 7IPM. (This will obviously vary on the machine your running it on.) I run my parts on a Nakamura-Tome WT-300. I tend to lean towards Kennametal or Sandvik for my drilling. A little more $$$ up front, but tend to last longer.

Not sure if I am too late or not. But Kennametal makes a 1.025". Not sure if that really makes that big of a difference but it has a 1" shank on it. Kentip drill

Sorry for taking so long to get back at this. But Yes.... that would be correct. Now that I have ran the part several times with this mill. the tool works great, the tool life lacks a little but at those speeds who cares. THe BAD part is I have sent it to 4 different grind shops to have it reground and NO ONE can regrind it... The mills are getting pretty expensive with out a regrind... But I guess it comes down to time versus tool cost..

Stick with the Greenleaf... The composite make up in their ceramics are a ton better than Sandviks. I found when cutting the Ni materials by lowering the SFM and raising the Feed, i was getting better tool life and make a good chip. Just my 2 cents worth.

Well let me start at the beginning. At our shop we primarily use forgings and do not start from bar stock or flat stock. In Mastercam when i start to write a program i go to click the create stock. I pull an .stl file for my stock option. (instead of rectangle, cylindrical etc..) The material shows up on there but I can not machine on it. is there a way I can draw the stock to simulate my forging or is there any other way?

I have tried to import .stl files for stock and it shows up as stock, but for some reason my tool paths do not look correct at all. Is there a secret I am missing?? Thanks for any help you guys can provide.

Iscar just came out with a "Chatter Free" Mill. It was designed to compete against the varimill. I tested them here and have had great results. We were running in 718 Inconel at 250 SFM on a 3/4 " end mill. The good thing about this was we were able to take full cuts for slotting. (2-1/8" deep) I didnt believe the rep when he told me so I made him bring in a bunch of test tools. Pretty amazing. Now I do not know the details for regrinds, but my tool life was great. Hope this helps