Turpentine in Cutting Oil
When cutting steel or wrought iron in a lathe, milling machine, drill press or planer, it is sometimes necessary to leave a smooth surface. Oil, or various cutting compounds of oil, is used for this purpose and to keep the surface cool. If a little turpentine is added to the oil, it will greatly assist in leaving a smooth surface. A proportion of one-quarter turpentine is good.