A mold insert (12) is held down in a mold base (16), released, and then ejected upwardly, by positioners (30, 32) that each includes a lock member (50) and an eject member (52). The mold insert has a recess (40) in each side along its front portion and has a largely downwardly-facing shoulder (42) at each side along the rearward portion thereof. Two largely cylindrical bores (44, 46) are formed in the mold base and each communicates with the recess and shoulder at each side of the mold insert. When the lock member is pivoted about the bore axis (54,56), a lock part (74) is moved out of the recess in the mold insert to allow the mold insert to move up out of the mold base. When the ejector member is pivoted about the bore axis, a radially-projecting ejector part (80) moves upwardly against the shoulder on the mold insert to push up the mold insert so its upper end lies above the mold base and can be lifted out.