Using a fluid when sharpening on a stone is a good idea. For diamond stones, water is recommended. But sometimes people wonder if oil can be used instead. The answer is yes, but it’s not the best choice.
Oil is usually used with stones like Arkansas, Crystolon, or India stones, which are known as oil stones. Oil seeps into the pores of these stones and stays there, preventing clogging and not harming the stone. Water can also be used with these stones, but it doesn’t offer lasting benefits because the stone dries between uses.
Using oil on a diamond stone won’t have the same effect because diamond stones don’t have pores to absorb it like oil stones do. Oil will just sit on the surface, making the stone slippery and spreading everywhere. Water is better because it’s cleaner and oil doesn’t give an advantage.
If you do use oil on your diamond stones, only use a non-hardening oil like mineral oil. Vegetable oils that harden should be avoided because they’ll make a sticky mess that’s hard to clean. Also, avoid oils that aren’t refined or have thinners or solvents, especially with interrupted surface diamond stones mounted on plastic. While it’s unlikely that solvents in the oil will react with the plastic, it’s better not to take the risk.
Lastly, if you use diamond stones to flatten water stones, make sure they’re completely free of oil first. Clean them with a degreaser or detergent if needed because any oil left on the diamond stone can transfer to the water stone, and water and oil don’t mix well.
