I have had good luck with Marine Tuf-Cloth.
I use it on most of my blades here in South Florida, including several carbon steel neck knives.
I usually apply it and let it sit for a while until it dries thoroughly. Often on carbon steel blades, I'll apply it on consecutive days to ensure that the blade has been well coated.
I have had no rust problems since using this product. I have had a patina develop on some carbon steel, but no red rust at all.
Blues
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