The only thing I've had to clean is the ring on an eVic after liquid leaked from an RDA. Take the battery out, dump some isopropyl in it, move the ring, dump some more, move some more, let dry, see if it's still sticky.
And 510 threads in eGo batteries, wipe out with a paper towel.
Other than eVics all I have is stainless and a brass mech. There's no care needed. eVics are anodized aluminum which you don't want to polish.
I embrace the nature of brass, just like I'd do if I had copper.
This is how I'd polish if I were to polish. Polishing Stainless is a pain with a polishing machine, can't imagine attempting it by hand. I've only had to do it after I've done some modding on a cap.
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