Driver Gear Effect Question

[Mad Hatter]

Question for Brian and everyone else:

If the center of gravity is exactly in the center of a driver.
With everything else being the same path, face, hsp, vsp etc
If a ball is struck a 1/4" towards the toe and a second shot is struck 1/4' towards the heel.
Will the spin axis be the same amount but in opposite directions?

Example
Toe hit would give a spin axis of -2.5
Heel hit would produce a spin axis of +2.5

 

[Kevin Shields]

I dont know for sure but in the real world arent most toe hits a little high on the face (less spin) and heel hits a little low (more spin)?

Good question though.

 

[ggsjpc]

Great reply Kevin.

Gear Effect is 3d as Kevin mentioned.

 

[Frans@France]

Question for Brian and everyone else:

If the center of gravity is exactly in the center of a driver.
With everything else being the same path, face, hsp, vsp etc
If a ball is struck a 1/4" towards the toe and a second shot is struck 1/4' towards the heel.
Will the spin axis be the same amount but in opposite directions?

Example
Toe hit would give a spin axis of -2.5
Heel hit would produce a spin axis of +2.5

impossible to say because it depends totally on the values of the swing. Just one example to complement the remark made by Kevin : If the Lie of the club (including drop) is not the same as the swing plane angle then the toe is either up and the heel down or visa-versa. So spin-axis can then not be the same

Same can be said if the driver is not face neutral but 0.5 closed or when the AoA is negative or positive etc..

In short : When the clubhead would be fixed level and we would fire balls next to the sweetspot then all will be equal and the values found will be equal for both heel and toe.

If it was however in a swing I do not know if there is still some significant influence of the tip part of the shaft. Most books regards the head at impact as a free object but whether that is only true for center impact I don't know.