Abstract: The present quick-change mandrel for attaching a hole saw to an electric drill has different sized oblong locking segments at its front end which match the usual oblong openings in the back of different sized hole saws. The hole saw is slid rearward over the corresponding locking segment and then is turned in peripheral grooves in that locking segment to engage behind rearwardly-facing shoulders on the locking segment. The reaction force on the hole saw when it is cutting into a workpiece forces it more tightly in the grooves.