Hastelloy Threading

[bobcable]

Wondering if anyone has any advice for single point external threading hastelloy(a nickel alloy). I am using Kennametal style NTP3R KC5025. I get decent life for hastelloy but my threads continually come out torn up. Heavy cuts just aren't feasible as it rounds the insert over. Would love to hear if anyone has had better results. I have also turned hastelloy extensively so if anyone is interested in those parameters let me know and I will post them up.
thanks in advance for any help!

[beege]

What are you using for thread lube?

[bobcable]

Coolant- Hangsterfers S500

[Delw]

Bob

I dont remeber cutting threads on hastoly but cut it alot as well as other high nickle alloys inco stelite etc etc. on most we could not use the standard threading cycle(just drops down in the x, we had to use the one that varies in the z and x and i forgot which cycle that was, the coolant is fine thats all we used to run.
They did have to be light passes and we always used another tool holder with a thread tool for finishing.

if your running a non j thread your going to eat up alot of inserts and thread grinding would be the more economical way to go especially if its a fast lead

[bobcable]

Ya I upped my spindle speed to 2500 RPM take a very light .001 cut per pass a lot of passes but the insert lasted longer with some improvement on the looks of the thread. It will have to do for now, thread grinding just insn't an option for production of these parts.

[Delw]

Bob,
I am not sure what type of machine you have or if it is even possible,
when I was running Hitachi seike;s the thread canned cycles had like 4 of them.

one was standard straight down x move
one was sliding down the front part of the V
one was alternating
and the other was staggered?

I have the hitachi books with diagrams somewere just cant remember where , but the one that worked the best for high nickle alloys was the staggered alternating one, as it didnt put too much pressure on both sides of the insert causing the tip to wear faster.
I did a quick search online but couldnt find anything. I am sure they are somewere with explanations. I could have sworn when we had our supermax lathes with the OT control had 3 threading canned cycles also.

If your machine doesnt have the capabilities of this you can make your own using the g76/g33 canned cycle and even different tools to help you rough out the thread better and using the expensive threading inserts for a finish pass. of coarse this depends on your thread lead and thread depth.

VNGM inserts in a tool holder angle slightly has saved our butts many times for roughing coarse threads.

if you very the start point of your thread in your g76/g33 program and not go as deep that will rough stock out as well.
you said it was for production so it might be worth a shot.


Delw

[blowncoupe]

The one thing I learned from threading this stuff is to use cutting oil instead
of coolent.The threads were torn and ruff with coolent but with good grade of
cutting oil looked great