Cork Windmills

Cork Model

Using a cork as a spindle to attach blades is another idea we have seen in a variety of curriculum documents. While we have never used one like this before it certainly has promise if you are strapped for time and need a simple way to make turbines.

We have described one method. I am sure that there are many other ways to adapt this idea to attach 3 or 4 blades.

	Step #1 Drill a 4-5 mm hole through a cork (wine bottle, science cork, rubber ones do not work so well). Start small and make the hole larger if needed. A project vice is handy to hold the cork.

	Step #2 Cut sections of dowel or use a tinker toy stick. The diameter of the dowel should closely match the diameter of the hole you have drilled.

	Step #3 Insert the dowels into the holes that you have created in the cork. Make sure that they fit snuggly as this will be spinning fairly fast.

	Step #4 Mark the center of the cork with a pencil and using a pin prick a small hole. Firmly press the motor shaft into the hole. You can secure with glue. Once again a longer shaft will work better than a short one.


	Step #5 Attach blades to the dowels and insert dowels into the cork. They should be snug but you should also be able to change them fairly easily and angle them.

	Step #6 Now you need to attach this motor and spindle to a platform which will then be mounted to a tower. If you are building a model with gears or bands you'll probably want to mount your motor to a platform. If you do not plan on building a geared model you might try and use the simple PVC tower mount.

Check out this lesson plan from InfinitePower.org that is a variation on the same idea using a cork as a spindle. It is so simple that any student could do it!

Things to watch out for during construction:

Make sure to get the motor shaft as close to the middle as possible, otherwise you will get wobble as the blades spin. This can be bad!!
It may also help to cut the cork in half as that puts the weight of the blades closer to the motor shaft.
You can secure the motor to the tinker toy with some epoxy or hot glue. Don't add too much though or you will gum up the motor.
The strength of this model depends on the shaft length of your motor. The longer the shaft the stronger the connection! We have used the Motor 500 successfully, other DC motors have had issues because the shaft is too short.

Great!

Good

Kidwind Project
2093 Sargent Avenue
Saint Paul, MN 55105