Knurling 304 grade stainless ?

Hi,
I need to make a couple of knurled thumbscrews in a material that will resist corrosion in a boat where there will be exposure to damp sea air (but not salt
water immersion) and I wondered if anyone can tell me whether 304 is a suitable grade in terms of corrosion resistance and knurlability ?
If not then any suggestions gratefully received.
Thanks,
Boo
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wrote:

Hi I often make parts from stainless with knurls and I find that 304 is OK. 316 is the best grade from the corrosion point of view but the poor machining and higher cost are a considersation I also find it harder and much slower to knurl 316 Peter
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Boo wrote:

304 is just about OK for fresh water use, but it isn't much good if there is salt water anywhere near. Not really recommended.
316 is much better from a corrosion point of view, but it is a bit of a pig to machine, including knurling.
It can be done, but 316 is tough and sticky. Use sharp tooling, cut the screw blanks a bit more undersize than usual before using a sharp/new die (if you are going to tap them by hand, that is).
Take small cuts, and did I say use sharp tooling?
Knurling will take quite a bit of force.
316 is more expensive than 304, but for a couple of thumbscrews the cost difference shouldn't matter.
HTH,
-- Peter Fairbrother
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