As the old adage goes, "One man's trash is another man's yo-yo"... or at least, it's something like that...

The first time I got a yo-yo was actually when I was in the hospital. I got my first yo-yo not long before the holidays. I didn't use it right away, but I did, I was hooked. I never learned any super cool tricks or anything, but just messing around with it is plenty fun. I still have that yo-yo, but I wanted to challenge myself to figure out how to make one out of materials at my disposal (or even in it) so others could also make one for themselves and share that joy.

Step 1: Materials

Materials:

2 Aluminum cans (with the same diameter)
Corrugated Cardboard
Old pen/mechanical pencil
Paper
Yarn

Tools:

Drill
File/sandpaper
Hacksaw
Heavy duty scissors/tin snips
Hot glue gun
Ruler/Compass (circle drawing kind)
Scissors

Step 2: Axle

For the axle of the yo-yo, I used a mechanical pencil that I found in the garbage, but an old pen will work too, so long as the casing is a cylinder.

Remove the inner workings of whichever you choose- most have a way to unscrew or pull the insides out. Then, use a hacksaw to cut a section of the casing about 1 cm in length. Sandpaper or a file will work to remove excess bits and smooth the edges.

Step 3: String

For the yo-yo string, create a loop at one end of the yarn. I believe the name of the appropriate knot is an "overhand knot on a bight". It's not as complicated as it sounds; basically, make a loop and tie it around itself. You want this knot to fit comfortably around your index finger.

Measure about 40 inches from the knot and cut the string there. Use the last few inches to tie two half hitches around the axle or what's left of the pencil/pen used to make it if that's easier. If you choose to tie it around the writing utensil, simply slip the loop created off the pen/pencil and around the axle afterwards.

Step 4: Cutting the Cans Down to Size

The next step is to remove the bottoms of the cans. This can be done with tin snips or something similar. I used some ancient looking scissors I found in my attic. When cutting, be careful- razor sharp metal splinters have this nasty habit of mistaking fingers for pin cushions. Gloves are probably a good idea.

Once as much as possible is cut with scissors/tin snips, a file can be used to remove the rest of the excess aluminum. It's also important to file off any sharp or jagged pieces of metal. The remaining pieces should look something like tiny metal frisbees.

Step 5: Finding the Center, Drilling a Hole

Finding the center of the can bottoms is rather tricky no matter how you go about doing it. I think the best way is to place one needle of a compass where you think the center is and hold the other needle so it is just above the edge of the circle. Then, slowly rotate the compass. Identify specifically where the needle revolving around the other is furthest from the edge of the circle and move the center needle half that distance in that direction if the needle doesn't reach the edge, and in the opposite direction it if it reaches past. Repeat this process until the revolving needle stays perfectly over the edge of the circle. At that point, mark around the center needle with a pencil, or use the needle to poke a hole.

If you lack a compass, measure across the circle with a ruler until you find the largest distance from edge to edge. Make a mark at half the distance. Do this a few times to ensure it is center.

Drill a hole on the mark created so the axle can fit through snugly. I first drilled a hole with a 3/16 bit and worked my way up to a 21/64 bit, but your pen/pencil may be slightly larger or smaller so you may have to use a slightly larger or smaller bit.

Step 6: Gluing It All Together

Insert the axle through the can bottoms. Arrange it so there is an equal length of axle on each side and the aluminum pieces are held roughly .4 cm apart. When everything is in place (make sure the string is on the axle), make it permanent by applying a rather generous amount of hot glue around the axle on each side. Glue only on the outside of the yo-yo as to not interfere with the string.

The yo-yo should now have taken shape and even be able to return.

Step 7: Sides

For the sake of covering up the axle surrounded with hot glue, trace around the sides of the can bottoms on corrugated cardboard. Cut these circles out. Angle the scissors so the inner side of the cardboard is smaller (refer to pictures). Make sure these fit snugly in the aluminum pieces. Then, use hot glue spread around the inner sides to attach them.

To cover up the cardboard, I used paper. To do this, simply trace around the can bottoms again to form circles. Cut this out and use something like Elmer's school glue spread thinly over the cardboard to secure it. Use scissors to trim away any excess paper and cardboard.

Step 8: Giving It a Spin

At this point, the yo-yo is complete. All that's left to do is try it out!

With the loop around either the index or middle finger of the dominant hand, release the yo-yo until it's as far as it will go. Then, gently pull up. This should cause the yo-yo to return.

I hope you enjoyed this instructable. If you did, I would really appreciate if you would take the time to favorite it and share it with your friends. I'd love to answer any questions you may have in the comments below, or hear any suggestions you have. Thank you for reading this and I hope you'll be here for my next instructable!