Quote Originally Posted by cropwell View Post
So why does it not seem to be being used. Is the thermal transfer not good ?
Yep - just compare the specific heat capacity of water and your favorite oil. Oil does 'lubricate' better (i.e. lowers the co-efficient of friction between the tool and material more), so less heat is generated in the first place compared to with water, but I think that effect is only dominant for materials that are very hard to cut - i.e. the ones where people recommend using neat oil.