This video illustrates the low friction from a magnetic connection. The powerful Neodymium Magnets are rated at 87-112 pounds of pull force. I have smashed my fingers 4 times. They are really dangerous.
The balls are regular steel ball bearings and are NOT magnets. The smaller ones are 3/4 inch and the large ones are 2 inch x 2 pound steel ball bearings. They become magnetized when entering the magnetic field. The further away from the original magnetic field, the lower resistance the steel balls experience. There is an optimal distance based in the weight of the final ball. I am not sure what application this can be used for if any but it is quite amazing for a 5:37 hand spin.
