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Bernie Macdonald of Albion, California, developed the Electrilite personal transport vehicle. Here is a proposition for flexible fabrication of the critical components, the high-torque, low speed electric pancake hub motor and its respective motor controller. The natural spinoff of this enabling technology is three adaptations of the Electrilite:

  1. Pedal power assist electric vehicle, as in the prototype here
  2. Waste vegetable oil powered, Babington burner, flash steam hybrid electric vehicle
    1. Open source babington burner technology available, including flash steam generation and another digest here
    2. Electrilite hub motor is uses as an electrical generator
    3. Wheel motors power the car, and performance specification is a street vehicle
    4. Multi fuel capacity: gasoline, diesel, elcohol, waste oils, compressed gas, or others
  3. Hybrid electric tractor, with either battery or hybrid steam power
    1. 4 wheel drive

Business Model

The business model focuses on developing a low-cost, one-off fabrication capacity for electric motors, to be deployed as decentralized enterprise options for right livelihood, according to the principles of living described here.

The role of OSE will be to provide full technical support, enterprise training, and fabrication facility development. This may involve at-cost leasing of OSE's Compressed Earth Block press for structural masonry, or sawmill for lumber production. Equipment costs are as follows:

  • Lathe and multipurpose machining ability, utilizing the open source Multimachine (http://opensourcemachine.org) technology - $350
    • Engine blocks - $50
    • Engine rebore - $50
    • Bearings - $60
    • Shaft - $10
    • xy table - $70
    • Structural metal - $50
    • Bolts - $10
    • Lathe chuck - $50
  • Metal stamping jig - $300
  • Motor winding jig - $200
  • Balancing equipment - $200 for strobe light, computer oscilloscope, and piezoelectric sensor
  • Motor controller - electronics lab - $200 including circuit etching

Labor requirements for production of motors are approximately 8 hours.

OMNI Instruments will supply open source knowhow required for fabrication via technology transfer, to be negotiated.

Fabrication Capacity

Hub Motor


  1. Power scaleability in units of 5 hp
  2. Voltage adaptability, from 12-240 v or higher if needed
  3. Complete reversibility for function as a generator
  4. Power to weight ratio ~ 5 hp/10 lb

Currently, a prototype Brushless NFeB magnet motor drawing 75Amperes (max) at 48Volts is complete. Controllers provide incremental throttle with regenerative control braking.

Motor Fabrication Requirements

The main components for the electric motor are the shaft, ball bearings, armature, windings, and aluminum case. Ball bearnings, shaft, winding wire, armature sheet, and aluminum case are bought off shelf. The following fabrication capacity is to be developed in house:

  1. Casting for the case
    1. Feasible technology is a simple Babington oil burner furnace
    2. Casting molds may be produced by sand casting
    3. Casting setup costs:
      1. Compressed air for furnace:
        1. $30 at Surpluscenter- .18 CFM at 20 PSI
        2. $55, 2 CFM at 15 psi; 3 hp head, $100; 1.5 hp, $90; 1 hp, $110
        3. 1/3 hp electric motor at <$50 from Habitat Re-Store or Surpluscenter
      2. Simple aluminum casting furnace - $100
        1. Good links at backyardmetalcasting.com
  2. Stamping sheet metal for the winding core
    1. Stamping equipment - cost $?
  3. Motor winding
    1. Manual winding jig - cost $?
    2. Automated winding jig - sost $?

Material Costs

  1. 25 magnets at under $1 each, $20
  2. Shaft - $5
  3. Winding wire - $10/motor
  4. Winding core - $5 material cost
  5. Bearings - $5 each, $8
  6. Collars - 2, total $2
  7. Hall effect sensor probes - $10
  8. Other electronic components - $10
  9. Case aluminum - $3

Total material costs: $73 per motor

Testing Procedures

Dynamic balancing is required. The balancing setup for this includes a balancing jig, oscilloscope, piezoelecttric sensor, and a strobe light. Power output is measured via ?