Build a Model Turbine: Ride the Wind!^TM
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Savonius Wind Turbine

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Build It!

The Pembina Institute

Important note:

Please read and follow these instructions carefully, step by step! Have a one member of your group read each step aloud to be sure the instructions are clearly understood. Do not proceed until each step has been completed.

Tools Scissors Utility knife Hot glue gun and glue sticks Metal or plastic ruler Robertson screwdriver, no. 2 Pencil Electrical tape Digital voltmeter with probes equipped with alligator clips 4 rare earth magnets Push pin Pencil sharpener Sand paper or emery cloth

Materials 1.5-litre plastic water bottle Large piece of corrugated cardboard (approx. 60 cm by 40 cm, cut with corrugations running its length) Wooden base (plywood, particle board, or solid wood, approx. 14cm by 30 cm, at least 15mm thick) 1 wood screw (#8, 3/4" Robertson) Wooden dowel, 30 cm by 6 mm (1/4") Magnet wire (100m, 24 gauge enamel coated) Rectangle of corrugated cardboard, 4cm by 16 cm cut with corrugations running perpendicular to the long axis of the rectangle. White glue Nail or awl Paper Templates: Please download the following templates separately, and print according to printing instructions. Printing Instructions [PDF Format - 37 Kb] Base [PDF Format - 131 Kb] Frame [PDF Format - 179 Kb] Rotor [PDF Format - 113 Kb]

1. Prepare the Templates
   Included with these instructions are three paper templates, labeled "Base, Frame, and Rotor". These need to be glued down on either cardboard or wood before you can proceed with the assembly of your turbine.

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1. Cut out the "Base Template" to fit the rectangular base board using your scissors.
2. Apply a very thin, even layer of white glue to the back of the paper "Base template", being sure to cover the entire back surface of the template. Apply the template to the wooden board, and set it aside to dry.
3. Cut out the 3 pieces of the frame template and the parts from the "Rotor templates" sheet.
4. Apply a thin layer of white glue to the back of the paper "Frame templates" and "Rotor templates", carefully place on cardboard, and let dry. As you glue down the frame templates, be sure their long axis is parallel to the corrugations in the cardboard.
1. Assemble the Frame

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The Pembina Institute

The Pembina Institute

3. 
   The frame of your turbine consists of 4 parts: the top and two side pieces made of corrugated cardboard, and the base, which is from a short piece of plywood or 2 by 6 lumber.

D. CAUTION! The utility knife is sharp, and can cause serious cuts. Extend the blade only as far as needed to cut through the cardboard, and lock the blade in place!

1. Cut out the sides and tops of the frame pieces using the utility knife. The metal ruler can be used to help make the cuts straight. You may use the bottom surface of the board as a cutting board to prevent damage to the tabletop.
2. Using a nail or awl, make a small hole in the center of the wooden base. Turn the screw into the wood so that it projects above the board by about 4mm.
3. Set the blade of the utility knife so that it projects about 2 mm from the handle, and make shallow cuts along the dotted lines on the frame parts where shown. The cuts allow the cardboard to bend smoothly along straight lines.
4. Gently bend the frame parts as shown.
5. Glue the uprights to the board at the locations shown on the base template using hot glue.
6. Score and bend the top frame support so that it spans the distance between the two side pieces. The pinhole should be centered directly over the screw. Use a drop of hot glue on each side support to hold the top support in place.

5. Assemble and Mount the Coils

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The Pembina Institute

1. Make a winding jig by folding a small piece of corrugated cardboard in half and securing with tape. The jig should measure 3cm by 8 cm when completed.
2. Cut 8 short (4 cm) strips of electrical tape, and set them aside.
3. Leaving a wire lead of about 5 cm, start winding the first coil on the jig. Form a compact coil with 200 turns of wire, ending with another 5 cm lead. Cut the wire with wire cutters or scissors.
4. Carefully slip the coil off the jig, and secure it on each side using the two strips of electrical tape.
5. Using a piece of sandpaper, remove the enamel insulation from the ends of each lead, exposing about 1 cm of bare wire.
6. Repeat steps 1 through 5 to make three more coils.
7. Loosely position all 4 coils on the base, according to the "clockwise" / "counterclockwise" markings on the base template. It helps to trace the path an electron might take through the coils, starting at one end. Ensure each coil is arranged so that an electron moving through the wire follows each coil, alternating between clockwise or counterclockwise directions.

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The Pembina Institute

8. When you are sure you have oriented the coils correctly, connect the ends of the wire coils by twisting the bared ends together tightly.
9. Check your connections: Set a multi-meter for measuring electrical resistance (Ohms). Connect the probes to the two free ends of the wires from the coils. A good connection should yield a resistance reading of 7 to 10 Ohms (a lower reading indicates an even better connection). A large reading means that you have a poor connection between two or more of your coils. You may need to check each connection individually, and re-sand the wires before reconnecting to ensure all the insulation has been removed.
10. Once you are confident the coils are properly positioned and connected, glue them down on the stator disk. Use a blob of hot glue under each to ensure they will not shift.

6. The Rotor
   The rotor is a rotating disk equipped with magnets. This disk will spin near the coils to induce an electrical current.

CAUTION: In this section you will be using the hot glue gun. Be careful not to get the hot glue on your skin--it burns!

1. Use a nail or an awl to punch a hole through the center of the cardboard rotor disk. Be careful not to bend or deform the cardboard while you are doing this.

Using a compass to identify the pole of a magnet.

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The Pembina Institute

2. Carefully separate the magnets (some magnets may very strong and may require a ruler to pry them apart.)
3. Identify the north pole on each magnet, and mark it with a felt pen. Some magnets may have a mark (a red dot or some other mark) to identify which surface is the north pole. If there is no mark, you may need to use a magnetic compass to help identify the poles.
4. Put a generous blob of hot glue on the center of the first circle and press a magnet down firmly onto the blob. Be sure mount the magnets so that their poles alternate, as shown on the template.
5. Do not mount the next magnet until the glue holding the first one is cooled properly.
6. The Turbine
1. Using a nail or awl, punch a hole in the middle of each turbine end piece as marked (this is where your wooden dowel will slide through).
2. Using the utility knife or scissors carefully cut the top and bottom off the plastic pop or water bottle, to make a cylinder with open ends.

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The Pembina Institute

3. With the scissors, cut the plastic cylinder lengthwise into two equal halves. These bottles usually have faint lines on their surfaces that show the edges of the mould used to make them. These lines make an excellent guide for cutting the bottle into two perfectly equal halves.
4. Check the fit of the end pieces of the turbine with the plastic cylinder halves. You may need to trim either the plastic or the cardboard to get a better fit.
5. Apply a "bead" of hot glue onto the curved edge of one of the cardboard end pieces. Quickly position one of the cylinder halves onto this edge, holding it steady for about 20 seconds while the glue cools and hardens.

CAUTION: Be sure to apply the glue to the cardboard and not the plastic! The hot glue will deform the plastic if applied directly, and make it difficult to assemble the turbine.

6. Apply glue to the second end piece, and position it onto the cylinder you glued in step 5.
7. Use

The Pembina Institute

The Pembina Institute

8. the glue gun to apply hot glue to the remaining halves of each end piece, then add the second cylinder. This operation may take two people, one to hold the partially assembled turbine, the other to position the plastic half-cylinder onto the hot-glued end piece.
9. Use a pencil sharpener to make a point on one end of the wooden dowel. Round off the point using the sandpaper.
10. Check the fit of the turbine shaft in the frame by placing its sharpened point in the center screw and standing it inside the frame. The top of the dowel should just fit under the top frame support. Cut the doweling as necessary using the utility knife.
11. Insert a push pin through the pinhole location and into the top of the dowel. The dowel should turn easily and freely inside the frame.
12. Remove the push pin, and remove the dowel from the frame. Carefully push the dowel through the nail holes in the end pieces of the turbine. Slide the turbine on the dowel so that about 3 cm of the dowel sticks out above the turbine end pieces.
13. Recheck the turbine vanes and shaft for fit inside the frame. The turbine vanes should spin easily without hitting the sides of the frame. Add a bead of hot glue to the top and bottom of the end pieces where the dowel comes through to fix the turbine vanes to the shaft. You are now ready for the final assembly and testing of your wind turbine!

8. Final Assembly
   The object of this stage is to position the magnet-equipped disk so it spins smoothly, and as close to the coils as possible. The closer they are to the coils, the more electricity they will make.

The magnets should pass as close to the coils as possible.

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The completed vertical axis turbine.

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1. Carefully push the pointed end of the turbine shaft through the top of the rotor disk at its exact center. The magnets should be facing down. Avoid bending the cardboard. Slide the disk so that about 2.5 cm of the dowel projects from the cardboard.
2. Check the position of the rotor disk on the dowel by placing it inside the frame and re-inserting the push pin. The magnets should turn freely without striking the coils or snagging the wire between them. If necessary, press the wires down and out of the way, and press the coils in to a flatter shape to ensure they do not interfere with the magnets.
3. The disk should spin smoothly without wobbling. If the disk wobbles, you will have to adjust the angle a bit. Make small adjustments to the height and angle of the disk so that it spins smoothly, and as close to the magnets as possible.
4. If you are satisfied with the position of the disk, add a bead of hot glue around the dowel where it comes through the top surface of the cardboard disk. You can do this without removing it from the frame. Recheck the rotor disk by spinning it. You can make small adjustments to the disk's position and angle as the glue sets.
5. After the hot glue cools, remove the rotor and turbine assembly from the frame. Reinforce the disk with an additional bead of hot glue applied to the shaft where it projects from the underside of the disk.
6. Reassemble the turbine and check again to make sure the clearance between the coils and magnets is correct. You can make further adjustments by turning the center screw out or in depending on whether you want to increase or decrease the clearance between the coils and the magnets.

Test It!

(Click to continue)

Download:
Wind Turbine Construction Plans  [PDF Format - 827 Kb]
Printing Instructions for Templates [PDF Format - 37 Kb]

Paper Templates:
Base  [PDF Format - 131 Kb]
Frame [PDF Format - 179 Kb]
Rotor [PDF Format - 37 Kb]

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