RAIL GUN Homopolar motor high acceleration Science experiment

This is another version of the homopolar motor, in this magnetic experiment use an external energy source to have a greater acceleration effect. I use a 10V 15A power supply, but you can use a simple 9V battery.
The engine is a simple screw with magnets at the ends. The polarity of the magnets is very important. I try to outline the position.

S-N iron N-S (With this configuration wheel on one side)
N-S iron S-N (With this configuration wheel on the other side)
S-N iron S-N (Do Not work)
N-S iron N-S (Do Not work)

The aluminum foil transmits the current to the motor. The interaction between the magnetic field created by the current and the magnetic field of the neodymium magnets moves quickly the rotor.

I used 8 neodymium magnets 10x1mm