304 Stainless Turning Feeds and Speeds

I am turning some 304 stainless, 45mm diameter in a type 2 roughing cycle on a Haas ST20Y lathe with live tooling and a y axis. I am using a DNMG 432 insert in a MDJNL16-4D holder for both the roughing and finish operation. The part is a one off. I've written the program, cut one part and was not happy with the finish. So I'm asking for the most optimal feeds and speeds for my application. What spindle speed, depth of cut, and feedrate should be optimal for my roughing, and also my finishing. Any help would be appreciated.. I have 5" hanging out of my jaws. and it also cuts some flats with live tooling with alot of vibration.

You could tell us what you've already tried... And what was wrong with the finish...

I'm sort of a newb when it comes to lathes, but I'd look up the manufacturers info on the insert you're using and run everything near the high end of the scale. At least SFM wise. There's not much need to concern yourself with tool life on a one or two off, and I believe things cut better going fast then they do slow. Especially in finish cuts. And if your machine's a little loose, be sure to leave yourself enough meat to cut in your finish pass. Helps to tighten the machine up when it has more work to do. Then of course obey the rules on nose radius and feed.

On the live tool stuff, if those flats are on the end of your part I'd say you're pushing it stick-out wise without support. 45mm seems or looks stout, but things go south fast with stick-out. If there's no other way, you might try CO HSS for your end mill. Let some of that flex give way through the cutter instead of all of it through the work piece and setup.