PURPOSE: To manufacture a coil-end spacer for a generator or a motor, having excellent mechanical strength, without using a precision molds, by filling a mixture of quartz grains and a heat-resistant epoxy resin in a mold, and heat-curing the mixture after slitting.

CONSTITUTION: A mixture comprising 1 part of quartz grains (20-80 mesh) and 0.1-0.4 part, pref. 0.15-0.35 part of a heat-resistant epoxy resin, is filled in a frame made of phenolic resin treated its surface with a release agent, and having a dimension equal to that of the spacer. After smoothing the surface of the mixture at the level of the upper edge of the frame, the frame is removed, and the mixture is slitted with a cutter to the width of the spacer. The slitted mixture is cured by heating in a drier to obtain quartz-rich spacers.