[billbo911]

Originally Posted by Matt Howard

Now that this thread has been completely hijacked by an Ego contest....


When I built my air cannon in high school, I had the help of my father who has worked in Water Treatment for about 30 years, so thankfully I was blessed with knowledge from above about pressure ratings.

I used 4 inch Galvanized Steel, and typically ran it at 135 PSI.

I was able to launch aluminum baseball bats about 250 yards with about a gallon of water in the barrel.

Enjoy some very dated pictures:

The wisdom to take from this post is that the pressure tank was built out of steel, not PVC. Secondly, from the looks of what was built, I would say it really didn't cost that much to build either, and could be easily reproduced.

Now my next question.
From the looks of the pictures, that shattered bat happened before it hit the ground. Take a close look a the bottom of the picture showing the canon firing. Look at the shadow, it looks like the bat has broken already. Is this correct?


BTW, I love the use of water to seal around the bat and act as a sort of Sabot! Besides, it looks AWESOME!