Launcher Built

I need a website or an idea on how to build a "simple" tennis ball launcher ?

This must include the preliminary desgn and step-by-step proceedures, also with the list of the materials.

I think you can construct something somewhat close to a rail-slingshot that can at least fire at a range of 25 feet depending on the maximum trig of the distance (until maximum stress). Or you can use air pressure. However, enabling air to chamber through the elastic pump- sort of like a water gun. The air travels through the first chamber which pressurizes the air through the near stress trig of the elastic pump position. So, I doubt that it is possible with household supplies. Try this: Cut open the main tape (if unopened), and cut open the tube so that on both sides are open. Then, find a few strips of flexible poor metal composites and tape it to the maxims of the sides (furthest sides). Get several- up to 12 rubber bands with about the same radius maxim and amplified energy trigger- I suggest you to get the furthest radius in the center- and stretch them across the tennis ball container. fold the metal extents and tape them into the center. Now you have a basic tennis "launcher".

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