pic: Pneumatic Kicker Rev_1

A cleaner kicker prototype we rigged today. Has a few kinks, less power than the wood prototype. Maybe a heavier head at the bottom? Or perhaps scrapped? If anyone finds a superior way to apply this method please let us know.

Three suggestions:

  1. Try a smaller diameter cylinder. The reduced cross-section means you need less air to actuate the cylinder. For a given charge of air, you will get a faster response (up to a limit, as the high pressure wave through the tubing approaches supersonic speeds). There will be a transition point where the diameter reduction will result in less power transferred to the ball during the impact, but I think you are nowhere near that point yet.

  2. Try a lighter hammer. This may seem counter-intuitive, but it works. Talk with your physics teachers about this.

  3. Pre-load the lever arm with surgical tubing to augment the striking force of the cylinder.


We originally had it set with a smaller piston for that very reason. This image is when we were attaching a larger bore size in order to handle a possible surgical tubing augmentation. The smaller piston cant pull back the tubing very far…but that might just be due to our configuration.

As for your second suggestion regarding the weight of the hammer…I’m rather intrigued. We were under the impression the weight was applying a large portion of the force against the ball…


dave lavery!!!

You’re quite literally AWESOME.

this seems like something i tried but with a shoe. but mine failed.

Did you assume that the smaller bore cylinder could not pull back the surgical tubing, or was it tested? Yesterday I found a list of bore sizes, PSI, and the force each one can exert. It can be found here:


on page 15.

Your power loss on the metal versus wood may have to do with the placement of the cylinder. It appears that on the wood model the cylinder is positioned to pull the hammer back and get a swing on the ball. While in the metal version it appears to start in contact with the ball and just push it.