Lapping Machine

a metal cutting machine tool for fine finishing (grinding and lapping) of flat and cylindrical surfaces using laps with surfaces coated with polishing or grinding materials. Vertical lapping machines are used for finishing external surfaces, and horizontal lapping machines for both external and internal surfaces. A vertical lapping machine has one or two metal lapping disks. The workpiece to be finished is placed between these disks in an eccentrically placed retainer (work-holder). The laps rotate at varying rates either in one direction or in opposite directions as the retainer undergoes an oscillating motion in the horizontal plane. As a result of the complex motion of the surfaces being finished with respect to the laps, uniform finishing and high precision of shape (tolerances to within 1–3 microns) are obtained. Surface roughness up to class 14 can be obtained using lapping machines.