Procedure
We didn't actually make any adjustments once our catapult was built except for the trigger that we needed. Everything else we tested with different materials and procedures while we were building the piece. For example, the pouch we were going to use for our projectile we ended up making out of pipe cleaners and a lot of hot glue instead of using the bottom of a Dixie cup. For the "wings" that the rubber bands would be attached to, we had to add supports to because every time we would pull the rubber bands back, they would break off. We ended up just making the track for the projectile out of Popsicle sticks.
- Line up two Popsicle sticks side by side when they're laying down. Use hot glue to glue them together. Next grab two more Popsicle sticks and put them on their side on both sides of the two you just glued together so that they resemble railings. Glue them to the Popsicle sticks. You can do them one at a time.
- Now that you have your track, you need two more Popsicle sticks. These you are going to glue to the front of the track going outwards. While that is drying, break another Popsicle stick in half. These you are going to use as support. One end of your halved Popsicle stick is going to go against the railing of the track, and the other end is going to go against the "wings."
- Next you have to make your pouch. We used one pipe cleaner and rolled it up. From there you push the center outward until it resembles a cup of sorts. Leave that alone for a minute and grab a rubber band. You'll need to cut it in half. Next you have to weave it into your pouch so that there is a loose part on the back. Now you're going to need to put a lot of hot glue all over the back of the pouch. This is because if you'll notice, the pre-hot glued pouch is very malleable. The glue will stabilize the pouch. You need to have a loose bit of rubber band on the back of your pouch that you need to lace a piece of string through and tie.
- Now you will need to prop up your catapult. To get a 45 degree incline you will need to cut another Popsicle stick down to three inches and prop the end of your catapult up on that. I suggest putting all of this on a piece of cardboard.
- Finally you need to glue a clothespin down at the end of your track. Now you can clip the string from the end of the pouch onto the clothespin, load your projectile, and press the end of the clothespin to launch your catapult.
- Name your catapult and write it in fancy lettering on the cardboard.