Lately my thumb has been hanging in most of my thumbholes...grabbing on the inside pad between the knuckles.  I tried several different adjustments, but the only thing that seem to work was a wide bevel on the top half-inch of the thumbhole.  The lower half of my thumb still hangs in pretty strong so I'm not worried about dropping my ball, but the bevel lets my thumb out so much smoother.  I'm even getting the "pop" sound that I hear when watching the pros throw on TV.  I haven't seen any other bowlers using such a wide bevel at the top of their thumbholes and was just wondering if this is unusual or a bad thing to do.

Thanks in advance for your input.

Lefty
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220...221...whatever it takes.

Edited on 10/17/2008 9:42 AM

Also bear in mind that everybody's hand is shaped differently.  Some people need more bevel, no matter what the thumb pitch or span, just to accomodate the shape of the base of your thumb.  My mom, my dad, and I all need quite a bit of bevel because of the shapes of our thumbs to avoid unnecessary pressure on the inside base of the thumb.  Other people, however, can get away with almost zero bevel.

A couple of thoughts.  First, pitch and bevel work together.  An option to avoid the increased bevel would be to add some reverse pitch, maybe 1/8 or so.  Second, as others have said each thumb is shaped differently.  If yours is what we called "coned", meaning the base is significantly larger than the body, the hole needs to be drilled to fit the body of the thumb and the driller needs to open up the top inch or so of the hole with his bevel sander and use more bevel than normal.  Finally, the stiffness and hinge angle of the thumb are critical in getting a proper fit.  These can only be analyzed by checking them in person.  --  JohnP