The close-cut undercutter was specially designed to finish off a mica slot when it is necessary to cut within 1/8 Inch of a riser. This unit has a straight solid shaft and needle bearings, both front and rear, for smoother operation. Though we hesitate to recommend carbide saws in any hand-held undercutter, we have had success with them in this smaller unit. - While this small machine can be used for undercutting the full length of smaller commutator slots, one of the more substantial Martindale Undercutters should be used on larger commutators for most of the cut and Close-Cut used for the remaining end against the riser.