Whitworth 5" lathe, 1843

Whitworth 5" lathe, 1843

This 5 inch treadle lathe made by J. Whitworth & Co embodies the improvements introduced by Joseph Whitworth. His patent of 1835 included the split nut by which the lead-screw of a lathe could be engaged at will so that the carriage couId be caused to traverse and the mechanism by which the cross-feed could be actuated by the lead-screw. He also introduced the hollow box design of lathe bed, which is much more rigid weight for weight than the triangular bar construction of Maudslay's lathes besides giving protection to the lead-screw; and the conical headstock bearing, which takes end thrust.

This lathe exemplifies Whitworth's improvements. If the split nut is disengaged, the cross-feed motion may be obtained through a pinion meshing with the lead-screw. If, however, the cross-feed is thrown out of gear by the lever at the back of the carriage, the handle at the front may be used to give rapid traverse to the carriage. In this case the lead-screw functions as a rack. The treadle and flywheel of this lathe are missing and a dividing head has been added.