Definitions for "Leadscrew"
threaded shaft used to drive a carriage on a machine, eg. shaft used to drive the toolpost carriage on a lathe.
A leadscrew is a large screw used to actuate precise movements of the tool or the work when performing cutting or grinding operations on a machine tool. The precision of the surfaces of the parts made on the machine tool are limited by the precision in the surfaces of the machine tool's leadscrews. For this reason the threads of a leadscrew are made by an initial cutting operation, but the final surface is made by grinding.