Step 1: Supplies that you will need
1. 3 cardboard tubes or cans approximately 10 inches long by 2 1\2 inches in diameter(potato chip cans work well)
3.Duct tape or a strong type of tape
4.3\16-inch drill or punch
6. tennis ball
7. wooden stick about 12 inches long
8.Thin walled, 4-inch diameter pvc sewer pipe( length equal to length of cardboard tubes or cans)
9. sand paper or sander
Step 2: Making the Tennis Ball Montar
1.Pick one empty tube or can to be the base tube.On the tube or can, drill a clean 3\16 hole about one inch from the bottom.
2.On the other two tubes or cans,puncture the bottom end with a tin snips so that you have one round-shaped hole in the bottom.
(baffles are the key to a good mortar, so make your baffles carefully.)
3.File or sand the cut holes to dull them so they are safe to handle
4.Assemble the three cans or tubes to the correct order.To put them together, cover the entire assembly with no more than three layers of duct tape or strong tape. Make the seams between the cans or tubes airtight.(Be sure to leave the firing hole clear and open.)
5.Now make a PVC blast tube out of the 4inch PVC pipe.The PVC tube should be made just as long enough to contain the entire Tennis Ball Mortar when slipped in. Drill a large hole in the blast PVC tube that equals to the location of the firing hole.