Design Challenge 4.
Your teacher has volunteered to sit in a dunk tank to help raise money for TECA. As brilliant technology education students, you and your team have decided to design and fabricate a device that will propel a ball at the dunk tank release mechanism instead of manually throwing the ball to assure your teacher gets wet on a consistent basis.
Air powered ping-pong ball launcher
1. Take the 2 inch end cap and drill a hole so that you will just be able to stick the valve stem in to it. (Note: the valve stem has to fit very very snugly otherwise air will leak out). So you are better off starting out with a smaller hole than you think it should be and you will always be able to make it larger later.
2. Pull the valve stem though the end cap so that the fill end is on the outside of the end cap.
3. Glue the end cap on the end of the 2 foot section of pipe. Make sure not get any glue on the valve stem.
4. Glue that 2 inch slip to slip fitting to the other end of the of the 2 inch pipe.
5. Glue the reducer into the other side of the slip to slip
6. Cut a 3 inch section of the 1 1/2 pipe and glue this into the reducer.
7. Now glue the ball valve on the end of that section of pipe.
8. Cut another 3 inch section of the 1 1/2 pipe off and glue it into the other end of the ball valve.
9. Take the slip to threaded 1 1/2 inch inch female fitting and glue it on the end of the pipe.
10. Finally take the remaining amount of 1 1/2 inch pipe and glue the slip to threaded 1 1/2 inch male fitting to one end of it.
11. All you have to do is screw the barrel on to the chamber and your good to go. (Warning: Don't forget to let the glue dry sufficiently)