A cylinder of water 30 meters high, with a diameter of 3.57 meters, will have a mass of 300 metric tons.
This cylinder could be suspended from a vertically mounted rim with a mass of 5700 metric tons.
Three hundred tons would be accelerating 6000 tons: for an acceleration rate of (9.81/20) .4905 m/sec².
After the 300 tons has dropped .1 meter the 6000 tons will have a velocity of .3132 m/sec. From d = 1/2v²/a
This 1,879,255 (6,000,000 kg * .3132 m/sec) units of momentum could accelerate 77.46 metric tons to a velocity of 24.26 m/sec; by using the Dawn Mission despin event.
At 24.26 m/sec the 77.46 metric tons will rise 30 meters.
The 300 metric ton cylinder has only dropped .1 meter. Only 1 ton of the 77.46 tons is needed to refill the shallow void at the top of the cylinder. The shallow void has a volume of 1000 liters.
You now have an excess of 76 metric tons at the top of the cylinder.
The 'Delburt Phend double yo-yo despin' proves that the cylinder and spheres conserve Newtonian momentum not energy.