Posted by: Jack Mankin (brumil2@hotmail.com)) on Mon Jun 13 07:24:20 2005

>>> I think the back forearm and bat line up/get coplanar at/just after the bat is pointing back at the catcher and about 2 or 3 frames before contact (30fps) when the bathead leaves the arc of the handpath,roughly about 90 degrees from contact as in Bonds 01 or Glaus 02 or a frame or so (at 30fps) after this point:

http://sportsillustrated.cnn.com/baseball/mlb/features/2001/bonds/images/large/hr_61.jpg <<<

Hi Tom

In the pic you referred to, I can not believe you would say the plane of Bonds’ back-forearm is in the plane the bat is traveling. The plane of his swing (and bat) are angling downward (toward the catcher’s mitt) while his forearm is angling upward. The two planes intersect at about a 40-degree angle. Therefore, I must be misunderstanding your definition for the swing plane. Here is how I defined the swing plane. --- "Think of the plane of the swing as being a flat disc that is tilted down toward the plate so as to intersect the path of the ball in the contact zone. The bat, lead-arm and shoulders should all be in that plane from initiation to contact."

For the sake of clarity, would you give us your defination of it.

Jack Mankin