# YOYO

This project requires the use of a power tool. Therefore, it should be done only under the supervision of an adult.

Materials needed: Wood, electric drill, hole saw, dowel rod, paint, sandpaper, glue, string

Although it is relatively easy and inexpensive to purchase a yoyo, you may want the satisfaction of making one yourself. The picture above shows 4 homemade yoyos.

You can purchase a set of hole saws fairly inexpensively at a hardware or discount store. A set will consist of several sizes of blades and a mandrel for holding a blade.

You can use various thicknesses of wood and you can use any size hole saw. However, I suggest that you use wood that is one-half inch thick and that you use the 2.5 inch hole saw. The resulting yoyo will closely approximate the size of a commercial yoyo.

1. Use your hole saw to cut out two circular pieces of wood that will look something like the following illustration:

2. Use sandpaper to round over the edges so that they are smooth.

3. The next step is to mount the two disks on a dowel rod. The hole saw will have made a hole in the center of each disk and the hole is usually 0.25 inch in diameter. Therefore, you will need 0.25 inch dowel rod. The length of the dowel rod will be determined by the thickness of the wood that you have used. Let us say that you have used one-half inch wood as suggested. The dowel rod's length should be twice the thickness of the wood plus one-eighth inch. In this case the rod should be 1.125 inches.

4. Smooth the ends of the dowel with sandpaper and then place both disks on the rod as shown in the following picture. A drop of wood glue should be used to secure the disks to the rod.

5. Paint the yoyo any color that you wish.

6. After the paint is dry, attach a string. Tie a small loop in each end of the string. After making the loops, then create a larger loop as shown below.

The purpose of making these larger loops is to provide a method of attaching the string to the yoyo, and of attaching the string to your finger. Open one loop so that it is large enough to go around the yoyo and then drop it into the slot between the disks and tighten it so that it grips the dowel rod. Open the other loop enough to slip it on to your second finger. The length of the string depends on the height of the person using it. A suggested length is 3 inches more than the distance for your belt to the ground.

7. Wind the string into the slot. Then you can "throw" the yoyo so that it unwinds the string and then rewinds the string bringing the yoyo back to your hand.