I don't use mechanical pencils, but I do use the pencils with the little plastic inserts. When the point wears down the insert is removed and pushed into the top pushing a new tip to the bottom. Has worked pretty well for about 4000 dives.do the pencils fall apart after 3-4 dives? the pencils I use crack or split after 3-4 dives. Has anyone tried a mechinal pencil?