Having done some research, 304 seems to be a mixed-bag: it CAN be machined but it's far from a free-machining stainless steel. In fact, most stainless is harder to mill than, say, 1018 or even 4140.
But I know it CAN be machined. So I bought some 303 Stainless. It's easier to machine than 304 but far from "easy". Doing some research on speeds and feeds, it cut beautifully!
Watch along as we calculate feeds and speeds, discuss tips and tricks for machining stainless steel, then mill some on the Tormach PCNC CNC Mill!
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