Geoff:

I have devised this simple procedure to create a pure pendulum action and thus I believe isolating gravity within the putting stroke.

To do this experiment all you need is (a) a foot ruler, (b) 6 golf balls, (c) face-balanced putter ideally straight center-shafted and the longitudinal center of gravity axis close to the shaft axis. I used an older Bullseye putter with an ~ 77º lie angle. A level carpeted surface should provide consistency.

To achieve a pendulum stance, you cannot use the conventional high-low overlapping hand putter grip .... because the putter must hang freely vertical in your hands ... and offset hands cannot achieve this in a vertical plane. I devised a "Prayer Grip" where both hands symetrically faced each other and the putter was slipped in between so it was held by the base of the palms and only the long fingers (Digit III) touched the grip on each side. This creates a clamping of the top of the putter grip only ... at the base of the palms nearest the wrists and serves as a pivot point should the putter attempt to rotate near the wrists thus indicating that pendulum action has been breached. In this manner the putter hangs freely vertical.

Place the foot ruler on the ground facing you to measure the length of the backstroke. Take a wider stance to ensure stability for the pendulum with it's pivot in the upper torso. Allow the putter to hang freely vertical but with sufficient palm clamping pressure to stabilize the putter head. Keep your elbows close if not pressed into the torso. The toe of the putter will slightly clear the ground and decent sweet spot contact can still be made if the sole is adequately rockered. Place a ball at the end of the ruler and start with the putter head besides, not over, the ruler which is only to be used for backstroke distance. You are now prepared to commence the putting test.

The lead hand will provide the initial torque to the putter grip to push it back the 12". The pressure should be mostly felt in the long finger of the lead hand as the putter is moved back, and, when the desired 12" has been nearly reached, the lead hand long finger pressure should be released by simply withdrawing the finger slightly, and this will signal that stop reversal point for the pendulum is being approached. The rear hand long finger in gentle contact with the putter grip should not experience any increased pressure at any time otherwise this would indicate that either a decelerative force was applied at the end of the backstroke, or a downstroke torque was applied. The free-fall of the pendulum putter commences from the stop reversal point.

This gravity stroking should be first tested without a ball to get the feel of the mechanics of the motion. Full cycle pendulum action can be tried, but the actual putting stroke requires that the putter start from a still position at the bottom, pushed back, allowed to find it's maximum backstroke distance and then released to freely fall to impact in a vertical pendular position. What you may experience is that to "ride" the putter in the downstroke you must ensure that there are no extraneous forces transmitted through the long finders or the palm grip on each side of the putter. You must anticipate the downstroke torquing of your shoulders and torso before reaching stop reverse so as not to create counterforces to the pendulum through the hands. You will feel this in your hands as you attempt to maintain a relaxed neutral balance as gravity-sponsored momentum takes over at the end of the backstroke and into the downstroke.

My own test results were quite consistent when putting in this manner on a uniform carpet. The balls all clustered around the same putt distances for acceptable stroking action. I rejected results that were obviously bad putts and not near perfect pendulum stroked.

For 12" backstroke, the balls all clustered around 42" (+/- 6") ... and for 6" backstroke they were at 18" (+/-3"). I was satisfied that all reasonable parameters where met and that the balls were solidly struck. Interestingly, the sensation that the initial torque applied to start the backstroke was consistent with the desired distances putt. I would call this "personal feel".

Geoff ... does this experiment satisfy your concept of the "gravity-sponsored" putting stroke? I devised this experiment to remove the constant cantilevering forces on the putter due to it's shaft lie angle, and to approximate pure vertical putting where only gravity is applicable. I believe I have reasonably isolated gravity as a putting force. Now the question emerges .... if I can only get a 3 1/2' gravity putt with a 12" stroke, how long of a backstroke is required for say 10' - 20' putts only depending on gravity ?

Dare I say that significant torque must be applied and to mix with gravity ... because stroking more than 12" becomes somewhat unstable ???

Dear Sammy,

If you are trying to prove to me that your notion of torquing down is absolutely required in putting, you have not succeeded. You have the two common misconceptions, even if your experiment is validly conceived and executed: 1. there is something inadquate for a 12" backstroke only sending a ball 3.5 feet across a carpet; and 2. "stroking more than 12" becomes somewhat unstable".

Why do you believe these two propositions?

My core putt, with a backstroke just outside my rear foot, usually sends the balls rolling 10-12 feet on a normal green. I have no idea what is the condition of your carpet, and I also really cannot see what it is you are doing to make the stroke. Your description is very difficult to envision. All this talk about fingers means next to nothing to me for movement, as the hands as a whole are moved by the arms, and the arms are moved by the shoulders, etc. I can't tell what you mean to be happening in terms of movement of the human body.

A very simple exercise is to suspend your putter by the tips of your thumb and index finger of the left hand, draw it back 12" with the other hand, and let it go, swinging down into a ball at the bottom of the stroke. On my carpet, the balls roll at least 6 feet.

In my experience, the stroke on most greens for a 15 foot putt is not the least unstable, nor is the stroke for a 40 foot putt. Human balance and smoothness is not at all challenged when the movement is nice and easy. The belief is widely held in golf that a long backstroke "creates a bigger oppportunity to mess up the stroke" -- as it is commonly expressed. That's probably true for hack golfers, but not for expert putters. This common notion becomes transformed into "cousin" propositions like the one you express: "a stroke longer than 12" is an unstable stroke".

I don't dismiss this notion out of hand. Instead, I also used to accept this and for years putted with a rigorously controlled, short, abrupt hit stroke. I was very, very good with it for distance, too, routinely sinking 40-50 footers. But thru the years of constant experimentation, I abandoned this notion as worthless tripe. After years and years of steady comparisons of quick strokes and slow strokes, I can safely tell you there is no comparison -- a slow, even-tempo stroke (even if long by common standards) is far more accurate and consistent. My proof of this is 16 years and nearly 4 million trials. Too bad you didn't have a clipboard handy while I was doing this -- you might be less bound up in the rudiments of physics when it is the human body that matters much more.

As you are aware, I don't really teach a gravity-only stroke -- I teach a gravity-sponsored stroke. There is indeed a torquing at the bottom of the stroke prior to impact -- a mild levering up thru the ball from the shoulder frame lifting and casting the putter head thru the ball. Your focus on the minutiae of physics in PART of the stroke misses the human action I am describing.

Cheers!

Geoff Mangum
Putting Coach and Theorist
PuttingZone
http://puttingzone.com>
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