I'm no clock expert but I do understand Physics.
Your question deals with the issue of torque. How much torque can the clock movement give to moving hands.
The maximum torque will be needed (for a clock running backwards) at the three o'clock position. Or depending how you number the clock its due right of the drive shaft.
At that point the torque is needed to raise the hand(s) upward. The amount needed is the product of the distance to the center of gravity of the hand TIMES the weight of the hand. You might measure it as inch ounces (inches x ounces).
Try this, estimate or weigh your proposed clock hand. Guess about where the center of gravity is (Its near the center of the cross section AREA of the hand). Calculate in inch ounces the torque needed.
Once you know that, make a trial hand from say some coat hanger wire. Make it long enough to hang the same amount of wood at that distance from the center. Try it out. Is the motor strong enough (Have sufficient torque) to lift the hand when it is due right of center. If it is, you got it.
I know, lengthy answer but I can't explain it any better than that.
