Making your own windmill can be a fun and educational project. However, without proper planning and design, you may end up with a windmill that is clunky, inefficient, and generally ineffective at harnessing wind energy. In this article, I will walk you through the process of intentionally building an amateurish windmill that looks neat but performs poorly.
Though a clunky windmill likely won’t generate much useful electricity, constructing one can still teach you a lot about mechanics, aerodynamics, and the challenges of wind energy. And you’ll end up with a decorative conversation piece! Just don’t expect your clumsy creation to meaningfully reduce your power bill.
To make your own rickety windmill, you will need the following materials:
- Wood – I recommend plywood, 2x4s, and other scrap lumbers for the tower and blades. Cedar and redwood are naturally rot-resistant woods good for outdoor use.
- Nails, screws, nuts, and bolts – Use a combination of fasteners to assemble the windmill. The connections don’t need to be sturdy or precise.
- Electric motor – A small DC motor will serve as your generator. A used or surplus motor with exposed wires works well.
- Blades – Almost any rigid, lightweight material can work for blades, such as sheet metal, plexiglass, or reinforced cardboard.
- Paint, stains, and sealants – Paint the wood to protect it from the elements and make your windmill aesthetically pleasing.
- Wire and electrical parts – You’ll need wires, alligator clips, switches, and other parts to connect your motor.
Optional materials that may come in handy include hinges, ball bearings, PVC pipe, and a decoy tailpiece. Don’t worry about finding optimized or balanced materials. Part of the goal is using scavenged parts and eyeballing measurements.
Build the Tower
The tower supports the windmill above obstructions and makes it visible. Use the following steps to construct a simple wooden tower:
Step 1: Make the Base
The base keeps the tower upright. Use four 2×4 beams arranged in a square to form the base. Nail, screw, or bolt the 2x4s together. Burying part of the base in the ground can provide more stability.
Step 2: Erect the Main Tower
Nail vertical 2x4s to the inside of the base at each corner. Attach two sets of 2x4s about 16 inches apart to make an A-frame tower. The height depends on the size of your windmill, but 10 to 15 feet is sufficient.
Step 3: Add Bracing
Use angled 2x4s halfway up the tower for reinforcement. Also place horizontal 2x4s in an X between the two A-frame legs for stability. The bracing does not need to be neat or precise.
Step 4: Attach the Motor Mount
Near the top of the tower, screw a flat platform made of plywood or scrap lumber to hold the motor. Place this mount at a height to allow your windmill blades to spin freely.
Assemble the Rotor
The rotor includes the blades and internal mechanics. Follow these steps to build a sloppy rotor:
Step 1: Determine Blade Length
The blades capture wind energy, so make them as long as you can without hitting the tower. For a small windmill, blades around 4 feet long should work.
Step 2: Cut Rough Blade Shapes
Use a jigsaw or handsaw to cut three long triangles out of plywood, sheet metal, plexiglass, or whatever material you are using. The blade shapes do not need to be identical or balanced.
Step 3: Attach Blades to Hub
Screw or bolt each blade to a central hub made from a circular piece of plywood. Space the blades evenly around the hub. The connections do not need to be snug or secure.
Step 4: Add a Tail
While optional, attaching a tailpiece helps orient the rotor into the wind. Use wood, sheet metal or fabric to make a tail and screw it onto the hub off-center.
Mount the Rotor
Mount your homemade rotor onto the tower’s motor platform:
Step 1: Attach the Motor
Screw the electric motor securely onto the center of the platform. Position it so the rotor axle can attach to the motor shaft.
Step 2: Place Rotor on Motor
Lift the rotor and place the hub over the motor shaft. Use a washer and bolt to loosely attach the hub to the shaft. It should still spin freely.
Step 3: Secure with Braces
Use wooden braces screwed into the platform around the motor to hold the rotor in place laterally. The braces only need to keep the rotor from sliding off.
Connect the Electrical System
The electrical system converts the rotor’s mechanical energy into electrical energy:
Step 1: Join Wires to Motor
Attach alligator clip wires to the two contacts on the motor shell. Run the wires down the tower and out through the base.
Step 2: Add a Switch
Connect the two wires to a switch. This allows you to turn on the circuit when the windmill is spinning.
Step 3: Connect Load
Run wires from the switch to your electrical load, like a light bulb, battery, or speaker. The system does not need to be watertight or safe.
To further guarantee your windmill underperforms, consider these additional measures:
- Paint the blades unevenly to unbalance the rotor
- Use a tail made of heavy material to place extra strain on the motor
- Mount the rotor at an angle to make it less aerodynamic
- Use thin bracing materials so the tower wobbles in wind
- Orient the windmill away from prevailing winds in your area
With creativity and corner-cutting, you can construct a windmill that looks neat but performs as poorly as possible! Just don’t expect it to meaningfully contribute to your energy generation.
Constructing a clunky, inefficient windmill might not be the best path to renewable energy, but it can be a fun learning process. Use scavenged materials, eyeball your measurements, disregard optimization, and avoid safety precautions. The result will be a visually impressive windmill that futily spins in the breeze without delivering useful electricity generation. While the output will be disappointing, you will gain hands-on knowledge of mechanics and wind energy principles. Just make sure your rickety creation does not become a hazard. And position it where visitors can enjoy its whimsical clunking!