Step 4: Making the machine (rotor)
2. After placing the shaft into the form, pour six inches of concrete tapping constantly to remove air bubbles.
3. Center the shaft in the form. Any circular flat item can be used. Drill a 1/2 inch hole in the middle and slide it over the rotor shaft and into the form. It should touch the outer edges of the form. Take measurements from the shaft to the outer edge to make adjustments to ensure that the rotor will spin true.