When finish gap milling stub axles, I used only 0.5 mm (0.0196 in.) of the corners on 22-mm (0.8661 in.) left-hand/right-hand triangular inserts, while the rest of their cutting surfaces—about 21 mm (0.8267 in.) went untouched. Instead of discarding these inserts after the corners wore out, I used the inserts for other jobs, such as machining rear axle halves to prepare them for being welded together. This idea works as long as the second use involves machining surfaces that are smaller in size than the untouched portions of the inserts.