How should I oil and store a T10 katana to prevent rust?
Updated Mar 2026
T10 carbon steel is not stainless and will develop surface oxidation without regular maintenance. Every two to three months - or after handling, since skin oils accelerate corrosion - apply a thin, even coat of choji oil or food-grade mineral oil using a soft, lint-free cloth, wiping from the habaki (blade collar) toward the tip. Avoid over-oiling, as excess oil trapped inside the natural wood saya can soften the wood's interior finish over time. Store the katana horizontally on a display stand in a room with stable humidity between 40-60%. Never seal it inside a plastic bag or airtight case, as trapped moisture dramatically increases rust risk on carbon steel surfaces.