The bottom end of the lap is held in a lathe collet & rotated at 110 rpm after applying the lapping compound. The liner is in position before turning on the spindle. I hold the liner with a leather gloved hand, moving very small amounts in & out. If you push in to hard the liner will lock up on the taper of the lap. Lapping with 5000 mesh diamond paste will give a mirror finish without a great deal of effort. Of course the liner must have a very smooth finish to start with before lapping.
