You have just three putted your third green of the round and your putter is about to take flight towards the woods. Has this happened to you before? Most of us have been in this situation. First putt is short, 2nd putt is over and only the 3rd putt finds the hole. You just can’t seem to roll the ball consistently.
When your ball comes to rest on the green it actually embeds itself slightly in the surface. Therefore, it is reasonable a putter requires a bit of loft to launch the ball out of its ‘nest’ but then we are interested in forward roll as soon as possible too. Too little loft and the ball will skid along and be easily diverted off line by any indentation. Too much and the ball will bounce along the patch. Both result in poor putting and a lot of frustration.
In physics, the force vector applied to the ball determines launch angle and ball spin:
- The effective loft at impact determines launch angle (appr. 80%)
- The difference between loft and rise determines ball spin (effective loft > rise = backspin, effective loft < rise = topspin)
So what is dynamic loft and rise angle?
Dynamic loft is defined as the loft at impact during the course of the swing compared to the original specifications. This can be due to the shaft angle at impact. The dynamic loft is mostly determining the launch angle of the ball. On faster greens (stimp 10-11) a dynamic loft of 2-3°is adequate, which means neutral shaft angle or slightly delofting a 3° loft putter. On fast greens less launch is needed (1-2°), on slow greens more launch is correct (3-4°).
Like any other clubs, the putter’s loft actually imparts backspin to the ball:
Rise angle is the path of your putter’s head when it impacts the ball. As loft introduces backspin, the rise angle should be higher than dynamic loft to impart topspin to the ball. Early roll is more important on fast greens compared to slower green and the preferred rise angle is 3-4 degrees upwards.
Rise angle impact topspin to the ball.
Here’s some high speed video to show the effect of loft and rise angle.
Example 1: Putting with neutral hands but loft higher than rise angle
Example 2: Added putter loft – low rise angle
Example 3: Delofted putter face – rise angle higher than effective loft