Repeating Vacuum Bazookas
The vacuum bazooka is a classic demonstration, you attach a vacuum cleaner to the side of one end of a pipe, cover the end with a piece of card and then drop a projectile down the other end and a the projectile flies down the tube and out the other end.
I got a bit carried away and worked out various ways of building repeating vacuum bazookas, because it sounded like fun (and because I could).
The Vacuum Revolver
This provides you 6 rounds of flying foam in quick sucession with a ratchet system, so repeatedly pulling a piece of string will fire all six rounds one after another.
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Showing the ratchet mechanism to fire the rounds | The whole vacuum revolver |
The Vaccuum Machine gun
For the times when 6 foam projectiles just aren't enough, there is the vacuum machine gun (ok maybe I got a little carried away...). This is a belt fed vacuum bazooka which will fire as many projectiles as the belt is long.
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The feed mechanism | From the front |
Here is a video of the vacuum bazookas in action...
The Vacuum Bazooka from The Royal Institution on Vimeo.