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304 SS varies widely. work hardened or cold rolled, cold worked 304 can easily be 200% more difficult to machine and if its full of larger hard spots or slag it can reduce tool life easily 10x. that is tooling cost can go up 1000% machining cheap 304 SS
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usually if you buy the cheapest 304SS if harder to machine it and it warps 10x more. tool life can often drop to below 30 minutes
Finally you write something I agree with. Sorry, I couldn't resist.
I hate 304, dealing with a lot of it at the moment, but am lucky it isn't in big quantities. Customer supplied material, cuts like concrete with HSS.
Kidding, of course, but it is definitely cheap material and it shows. Ran this 5 years ago and didn't have this much trouble with the material they gave me then, which was, at the time, from Brazil. This I suspect is Chinese.
To your question, don't expect to set any records in speed, variable helix endmills with high speed adaptive toolpaths can be your friend. But stay on the low side of recommendations you find, even lower than that, and you might be OK.
Traditional type toolpaths, insert tools might be ok, but as Ox said, don't use cheapo ones. I do not have any specific recommendations, sorry.
But I can tell you, if you deal with Iscar, who make pretty good tools, do NOT use their H490 type facemills. I love them, I really do, but they are only good in carbon/alloy steels. I've broken several inserts trying to use it for stainless. So I can only tell you to learn from my experience, don't waste your time with them.
If, tomorrow you have a batch of 4140 with a ton of facemilling, they are good tools...