PROJECTS: BOOM STICK
makezine.com/13/boomstick
BUILDING BOOM
The Boom Stick creates a pressurized volume of air and
releases it very quickly, generating a loud shockwave.
Piston
Air intake
1
HOW IT WORKS
To trigger
switch
Reservoir
Boom-valve
assembly
Piston check
valve with air-limiting holes
Piston
carrier
Manifold
Exhaust
valve
2
1. The piston rests in the
piston carrier, and the
entire system is at ambient air pressure. Small
holes in the piston allow
limited airflow through
from behind; a rubber
washer inside the piston
acts as a check valve,
passing air in only one
direction and increasing
efficiency.
2. When air flows in
behind the piston faster
than it leaks out of the
holes, pressure builds up
in the manifold.
3
3. Pressure behind the
piston pushes it into the
boom valve tube, sealing
the pathway between the
air supply and reservoir.
4. Pressurized air slowly
fills the reservoir through
the holes in the piston.
The cannon is loaded
once the pressures
between manifold and
reservoir balance.
4
5. To fire the cannon, a
small exhaust valve opens
and releases air pressure
behind the piston, draw-
ing the piston back into
the manifold. As soon
as the piston clears the
boom valve tube, the
pressurized contents of
the reservoir release into
the atmosphere with an
impressive bang.
5
Illustration by Damien Scogin
116 Make: Volume 13
