"Coolant" refers to emulsifiable oil mixed with water at around a 20 to 1 ratio. For best blade life this is what I would suggest using a squirt bottle occasionally. Heat is the number one enemy of any cutting tool so avoiding it will always benefit. Some lubricity is always beneficial so if all you got around is motor oil put a few drops or brush it on your drill bit or blade.






1952 1300 Canadian 1/2 ton restomod
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