[Daryl]

Mr. Kelley pointed out the Four Periods of Acceleration in Chapter 8. Shoulder Acceleration (8-7, Start Down), Hand Acceleration (8-8, Downstroke), Clubhead Acceleration (8-9, Release) and Ball Acceleration (8-10, Impact).

But what is Acceleration? Acceleration is the speed of speed or the change in Velocity per unit time. Velocity, however, has a directional characteristic. If an object has a constant direction (moving in a straight line) but its speed is increasing we have Acceleration. If the object is moving in a circular motion with a constant speed the Velocity is changing because its direction is changing..and we have an Acceleration perpendicular to the motion (opposite to the force you would feel if you where in a car) or toward the center.
If both your speed and direction where changing, again we would have Acceleration.

My Friend,

Hmm? Yes, 4 stages of Acceleration but I didn’t want to talk about the Ball. I never mix Theory and Reality. It takes too much of the fun away.

Yes, Homer Kelley called stage 2: Hand Acceleration. I chose to call Stage 2 Arm Acceleration.

I wonder if HK would care too much.

My reasoning is:

As the Right Shoulder Accelerates, it carries the Arms, Hands, Clubshaft and Clubhead along with it. They are accelerating, but not away from the Right Shoulder. From the Shoulders point of view, they haven't move a bit.

During Arm Acceleration, the Hands and Clubhead are accelerating also, but not away from the Arms. From the Arms point of view, the Hands and Clubhead are getting a great ride but have yet to contibute any gas money.

During Clubhead acceleration, the Clubhead is moving away, but it is not moving away from the Right Hand. From the Right Hands perspective, the Clubhead is not moving away, it’s only traveling more distance.

So I concluded that we cannot call stage 2 Hand Acceleration because Stage 3 Clubhead cannot move away (Accelerate) from the Hands, but the Clubhead can move away (Accelerate) from the Arms and the Arms can move away (Accelerate) from the Right Shoulder. I’m being petty.


Acceleration “by the numbers”: 6-C-2-B and 6-F-1
6-C-2-B ANGULAR ACCELERATION The Clubhead “overtaking” speed is governed by the Law of Conservation of Angular Momentum whereby the increased Mass resulting from any extension of the Swing Radius decelerates the hands and unless they are supported by Power Package Thrust (6-B-1) or Throw Out Action (2-K), can result in great loss of Clubhead Speed. Rely on Clubhead Lag to meter out the necessary support for the Primary Lever Assembly. Strictly speaking, any increase in the product of Mass times Velocity is Acceleration whether or not the Speed is changed. But the formula for Kinetic Energy gives Velocity the greater value. And, actually, the acceptable tolerance in the Ball-to-Clubhead weight ratio is quite small.

6-F-1 “RIGHT” TIMING Maximum Force is delivered by maximum Thrust (muscular and/or centrifugal) near – but prior to – full extension.
Acceleration ceases when the speed it has produced equals that of the Thrust, and though the Thrust is still present and able to maintain Velocity, it loses the flexed, stressed Clubshaft (Hitters) and the wallop of the Centrifugal Force (Swingers).