My now deceased m/l mentor was also a machinist/tool and die maker. He told me more than once that lard oil is the finest cutting oil known to man. Said he once was with Hacker Martin, in Hacker's shop in Gray, TN, watching him bore a m/l barrel with a brace and bit. He said he hit a spot where the bit stopped cutting as well as he wanted it to, and Hacker stopped, got some lard oil, put it down bore, and resumed boring.

SRH

May God bless America and those who defend her.