Problem- TURNING 17-4PH

[MoSHO93]

Having tough time. Turning a part out of 17-4ph. Insert life not very good. Its a 1." dia. stock only turning to .7865 leaving stock for grind. I have tried various speeds and feeds but only seem to get 40 to 50 parts per corner. Gone from 275sfm to 875sfm tool life didint seem to change much. Any ideas out there sure could use some help if you think should be getting better tool life.

[MJZAP]

Hi,
My opinion you are runing too fast. I'm useing SFM 160-220 and .01 in/rev.
Iscar inserts CNMG-432 TF IC907 and WORK GOOD.

Good Luck,
Max

[MoSHO93]

Thanks Max. What kind of tool life do you get. I am using Iscar cnmg-432 TF IC807. I have alot of these parts to run and think the boss would rather I use a few more corners on insert than run that slow. Im sure it would improve tool life but it would take me forever to run. Thanks I may try just to see how many more parts I would get per corner.

[MJZAP]

Not too many pieces. Its depend how long is piece and how many passes. This material is very gummy contains chromium and nickel need a lot of coolant. Big federate and small rpm.

Regards,
Max

[MoSHO93]

I'm hanging out 3 5/8 rough and finish end of part which has .125 radius on end that goes into 30 deg. angle which I run a little past the 1 inch stock then make one rough pass on o.d. then finish turn to .7865 then partoff. I went down to 235sfm but didnt get any better tool life. I'm running at 675sfm with good flood coolant, guess I'm happy with the 50 to 60 pcs. per corner. Was just wondering if it could be better. Thanks for your help Max.

[MJZAP]

Originally Posted by MoSHO93 . I'm running at 675sfm with good flood coolant,

WOW, that very fast. Let me know how many per corner.

Regards,
Max

[PixMan]

Walter grade WSM20, run at 850sfm (260m/m) in 17-4. Life measured as time-in-cut is 45 to 50 minutes per edge.

Let me know what your depth of cut and desired surface finish is, and I can suggest a chipbreaker and feedrate to use.