(under subclass 110) Lathe provided with: (a) a lead-screw integral with the lathe headstock spindle or relatively mounted on a stud projecting from the lathe bed wherein the lead screw is geared to said spindle in such position as to be readily engaged by a sectional nut at an end of a first lever whose opposite end is attached to a rockable chaser-bar mechanism, usually located at the back of the lathe bed, and (b) a second lever carried at another point of the first lever upon which is mounted a threading-tool.
