I am trying to cut some 420 SS that is 40 Rc. I keep burning up cutters. Corners keep breaking off.

I need some help on these issues:

types of cutters
speed and feeds
depths of cut
programming method

I would appreciate any help with this.

Thanks

Hanita Varimill... Mmmmm :D

'Rekd

Originally posted by MachineSMM

I need some help on these issues:

types of cutters
speed and feeds
depths of cut
programming method


Machine type?
Control?
Cadcam?
Tool Brand?

This is what needs to be addressed first.
What do you have?

I second the Hanita Varimill... Fantastic cutters. I cut 15-5PH stainless with them. Rockwell 40c . They ate it like butter. Even better when I ruffed the same material annealed it was the only cutter I found that wouldn't burn up and, they are very quiet. Great cutter design.

Difficult to cut stainless 250-280 SFM
.0025 chipload per tooth on 1/2 inch cutter.

Ken

What are you trying to cut?

Sorry, I knew I was forgetting some info.

We are milling.

We are making silicone rubber molds that are for the medical field.

The largest size mold we make is an 8x8.

Usually the cavity detail is pretty small. I do alot of milling of pockets for cores and cavity inserts. I would like to do some of the finishing work by milling instead of EDMing everything.

We do all of the cutting on a Haas VF2 with a 10,000 RPM spindle and a high speed control, or what they consider a high speed control.

I am using Mastercam

Right now I am trying out some mill monsters TIALN coated. It is not going to well.

I hope that is enough info.

Is it possible to give a little desc. of the cavity?
Can you post a screen shot of your model?
Or e-mail me so i can take a look at it and give
you a hand.

PEACE:D

Please elaborate on Hanita Varimill cutters. I'm an EDM idiot and i'm extremely dangerous when curious!!

Klox

The Hanita Varimill endmills also have an edge break on the corners but you won't have corners breaking off. These corners stay sharp and take alot of pressure. http://www.aronson-campbell.com/specials/apr2002.asp

I've had good luck with Iscar's 328 grade milling inserts on all types of stainless including 13-8 PH. I've found that the biggest mistake most people run into is not enough chip load which creates too much heat in the cutting zone. I think it was the RM designated ADKT 1505 inserts that we found to outlast everything that Sandvik, Kennametal and Seco had to offer. These had a pretty sharp ground edge which stopped the work hardening that we got with pressed inserts.

My advice would be to call the local reps and tell them to bring their best for the job you are doing. You never know......this can start a good battle for pride which could result in some free inserts or something. Good luck!

Adam

I would definitly try using the hanita varimills as well I have been using them to cut down a welded surface on a 304 stainless part, and was absulutly amazed by how much material could be removed without having to resharpen the mill.