Interaction of arm and club at wrist joint

In Figs 1 to 4 are incorporated the same type of information as in the diagram by Dr. Williams. The force vectors are shown in the top row and the corresponding magnitudes in the bottom row. 'Red' refers to force exerted on club, 'blue' refers to force exerted on arm.  Vertical axis -  force (N), horizontal axis - time (sec).

The central torque is constant and the wrist torque is modeled to form a 90 degrees dead stop to prevent back-knifing, hence no active wrist torque.
Up until t = 0 .15 sec the arm and club behave like a solid body but beyond the wrist joint is free.

Notice from Figs 1 and 2 that until t = 0.15 sec the tangential pull and centrifugal pull are the same.
Also from Fig 3 and 4 that centripetal inward tug and tangential inertial force are the same until t = 0.15 sec.

The only active torque is applied at the center. At the wrist joint there is a large action/reaction force developed during the down swing due to the nonlinear interaction of the respective motions of arm and club.  This action/reaction force is a vector and is projected in four different ways.  

1) perpendicular to arm.  ----------- Figs 1a and 1b   -   tangential hand pull
2) along the club, -------------------- Figs 2a and 2b   -   centrifugal pull on arm by club head
3) along the arm, ---------------------Figs 3a and 3b   -   centripetal inward tug towards center
4) perpendicular to club, ----------- Figs 4a and 4b   -   tangential inertial force on arm

mandrin

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