Catapult
A fun table top entertainment piece
The Base
First, you make the base. We designed the sides while we were designing the flat base part. This model is 6 inches by 4 inches, with a height of 4 inches. The over all thickness for this piece is 3/8 inches. After you have the side pieces made, you must put a circular hole in the center of both crossing spaces. If you are interested in a switch or button to pull or push to activate, you should make 2 half circles and attach them to the middle of the back side of the base.
The Arm
The arm is the most important part in the process. You are going to make a spoon shaped object. The length of this model is 7 5/8 inches long. The bucket of the arm is 2.36 inches in a trapezoid shape. The next trapezoid is a hole, this will be 2 inches. the body of the arm is 4.71 inches long with a width of 3/8 inches. There are two holes in the body, one on each end. The hole on the trapezoid end needs to be a little bit bigger than the one on the other end. Next is the square on the other end. There is a hole in the square that is 0.8 inches around. the hole is designed for weight. You need to place all the pieces together and then group them.
Time to Print.
Try to make the spoon as heavy as possible.
Final Touches
Place a dowel rod in the center of the holes in both sides of your base walls, and through the hole by the square. Place a rubber band in the hole close to the spoon. Add weight to the square. put a paperclip through the rubber band and the 2 rings. Load the spoon, pull the clip and watch it fly.