MetalworkingFun Forum

I need some hints on turning stainless steel. I've never machined it so I need some pointers on what to do and not to do. I have some 303 stainless steel that I will be working with.

Thanks,
Ed

Hi
Ed
303 stainless is great to machine
It likes heavy fast cuts
Depending on the power of your lathe the faster the better
Fantastic surface finish is easy to obtain
John

Ed,

303 free cutting - tends to cut very nicely.
I sometimes use a bit of cutting fluid, sometimes I don't, can be finished very nicely as well.
I'm talking turning, I haven't milled much of it.
It is the only stainless I machine now


DaveH

Edit, John copied my post Oh, seems I copied his post, we posted at the same time

OK guys, high RPMs it is and I always use cutting oil. What about cutting tools. Is HSS better or will insert tooling work and if it will, does one need an insert that is designed for stainless steel?

Thanks,

Ed

Ed
I use carbide insert tool for stainless
I have no idea what grade they are( they came in a plastic bag from a Friend)
I would think for what we are doing most inserts will do the job
It would be different in a production environment
Just play with feeds and speeds until it looks good
Dint be afraid to wind things up a bit
John

Thanks John, will do.

Ed

Hi,
I have 9/20 Lathe and matching size of Mill and turning and milling stainless quite often. I learned that using HSS to cut stainless -very low RPM and slow feed. Not very deep cuts naturally. HSS, High RPM and stainless steel just doesn’t go, no matter what ever the feed is.
I burned so many HSS and stopping the work and re sharpening them wasn’t much fun.
Now I am using carbide inserts, much better, comfortable feed and higher RPM’s and nice surfaces.
Ah! I also discovered and using Olive Oil for cutting fluid. I have tried all the others and none worked better. Yes! Plain “Olive Oil”. A drop of it to the tip of the carbide, at the beginning of the work, a drop at the middle and another drop for the finishing. (for medium size works) so, one liter goes for long ways (a year) at home shops. Especially for drilling stainless steel, it is ideal.
Instead of that acrid smell of stainless cutting fluid, you will have fried chips aroma around the shop as bonus.
It might be different for non-rubber stuff I don’t know

Unal

Unal,

Because different grades of stainless steels can exhibit quite different cutting characteristics, it is important to know the grade of the stainless steel to be machined.

DaveH

(05-25-2012, 08:18 PM)DaveH Wrote: [ -> ]Unal,

Because different grades of stainless steels can exhibit quite different cutting characteristics, it is important to know the grade of the stainless steel to be machined.

DaveH

I machined SS a few times a week years ago. VR Wesson was my favorite carbide and i slowed the lathe down and had no problems. I machined 304, 316 and Alloy 20 (Carpenter 20) for pump parts...Bob

Hi, Dave,

you have a point there. I have been using 303, 304 and 316 bars. I dont know any others, our local supplier carry only those.

Unal