After you try some different steel types you'll begin to see how differently they machine. I use a lot of 1018 cold roll steel and also alot of 303 stainless. The 1018 alway needs a little sandpaper to get a nice finish, the 303 machines smooth as glass, no sandpaper required. Huge difference in price though, a 10 foot lenght of 1/2" round 1018 is about $10 from General steel. I bought 10 feet of the same size of 303 from metal supermarket about 2 years ago for $80.
