Brian Manzella: 02/01/03 7:52:42 AM
At some point in the backswing the clubface opens, nearly 90 degrees to the target line by the top of the swing.
So it stands to reason that the clubface HAS to close on the downswing so that at the point that MATTERS (more on that in a second) the face is square for a straight shot.
It then continues to close past the ball to a certain point.
Now for what happens when the club hits the ball:
At impact the ball compreses on the face of the club and is carried along with the clubhead for about 3/4th of an inch.
So since the clubface has been closing to the point where it is square, the following absolute of geometry exists:
The clubface MUST be open at impact for a straight ball flight to occur (on any swing that includes an opening clubface on the backswing and a closing clubface on the downswing) The clubface needs to be about 3 or 4 degrees open, at impact, so that by the time the ball leaves the face, the face has "squared up."
Now for the exceptions:
Yes you CAN hit the ball with a square face and 'Hold" it square through the ball. Like Dave Pelz teaches in putting (this is called VERTICAL HINGING). If you did this on a full swing the ball would go much shorter than the opening and closing of horizontal hinging.
