Stainless choice for ease of finish quality

[dpb]

Have a small project, needing stainless steel. Will be facing, turning, drilling & tapping, all on a conventional lathe. Will be using 7/8ths round bar.
What is my best choice for material? There are no requirements for strength, corrosion resistance, etc. It just needs to be stainless, and look good.
I’ve done plenty of work with stainless, mostly 416r (rifle barrels), but I haven’t bought any for other projects.
Is 303 my best bet?

 

[mikey]

By far, 303 is the easiest to machine of the Austenitic stainless steels. It is my first choice when I need to use SS. 304 is harder to machine and work hardens easier and 316 is even worse.

 

[benmychree]

Mikey says it all! 303 is not recommended for welding, but can be successfully welded using tig and 304 filler, thing is, it tends to undercut at the margin of the weld bead.

 

[dpb]

No welding will be involved.
Recommendations for polishing the face (~.850 diameter)? I don’t have a polishing wheel, looking to put a good shine on it while still in the lathe.

 

[mikey]

If you're polishing for appearance then stepping up through the grits with sand paper works well. Then hit it with a polishing compound like Maas and it will be like a mirror. Make sure to cover your lathe bed first.

 

[P. Waller]

303 machines nicely but will not always produce the bright shiny finish that 304 will, more of a dull gray flat finish that does not refract light in color bands like 304 or 316 will after turning.

If finish is more important then machining time then stick with 304/316.