Mendocino Motor - 3D Printed

The Mendocino Motor

The Mendocino Motor is a magnetically levitated, solar powered electric motor.  It was first made by inventor Larry Spring of Mendocino County in California, for which it is named. it doesn’t have a real practical mechanical use, but is more of a novelty item for experimenting with rare earth magnets, electricity, solar panels, copper wire coil winding, and in this case designing 3D printed parts that will be the support structure for the motor.

There have been many modified versions of the motor concept that have been created as people have experimented with the motor components. My two versions are just a couple more of these modified experimental versions.

The design concept of the motor is to have a spinning rotor shaft that is held up by repelling magnets. Magnets are installed in the motor frame and on the shaft, thus creating repelling magnetic fields that levitate the motor shaft. With the repelling force of the magnets in the base, there has to be a stabilizing plate that extends up on one end of the motor frame. The pointed end of the spinning shaft then rests against this plate to hold the spinning rotor in place within the magnetic fields as the shaft turns. A 3D printed frame is mounted on the shaft to hold four solar panels in place, and to allow for copper wire to be wound in coils, just as it would be in an electric motor. When the shaft is placed in the proper position, and the motor is placed in direct sunlight, the solar panels generate electrical currents through the coils of insulated copper wire on the shaft. These electrical currents interact with another magnet in the motor base resulting in the rotation of the shaft.

How it works

My white 3D printed motor base has six locations for magnets. These magnets act as the levitation magnets which provide levitation when their magnetic fields repel the magnet fields of the magnets mounted on the motor shaft. A seventh magnet is mounted on the frame directly underneath the solar panel housing on the shaft. This is a field magnet which provides the magnetic field for the rotor. The end stabilizing plate has a thin piece of aluminum covering the front of the plate to act as a bearing. If this aluminum weren’t in place the 3D printed plate would eventually wear out. It also provides a smooth surface for the pointed end of the shaft to rotate against.

The black 3D printed motor base has only four locations for magnets. The rotor shaft on this motor has fewer coil windings and is lighter than the white one, which has many more coil windings making it heavier and requiring additional magnets to produce the levitation.

You will notice that the two motors have opposite directions of rotation. This is due to the coil windings and the sequence of connecting the solar panels to these coils. Since the black rotor is lighter it turns much faster than the white rotor. The video at the top of the page shows the rotors bobbing around. The rotors are normally more stable than what is shown. The video clips were taken outside with light winds. You can see this in the tree branch swaying in the video portion showing the white motor. The wind affected the shaft stability thus creating the bobbing.

Here are some close up photos of the white Mendocino Motor.