Launcher 2
Launcher 2
This is the second launcher we built.
Note that the launch tube itself is rather short here - about 20 cm.
Top view of the launcher with the U-shaped triggerpin that holds the bottle collar in place.
So far, this launcher has proven to be VERY reliable.
Again, it is made entirely out of 0.5" galvanized steel.
The trigger mechanism is a U-Pin. The U-Pin is held by 4 ringbolts, mounted on a nylon
plate. The nylon triggerplate is fixed to the tubing with tube clamps.
Thanks to the H-shape and very low profile, it is very robust.
At the corners of the H, we have 4 possible fixation points: one is used for the
manometer, another for the Schraeder valve. This leaves the 2 back endpoints free for
future extensions, like a booster tank or emergency valve.
At the back, you can see a tent peg, with a piece of orange nylon rope to secure the
launcher into the ground when pulling the trigger pin.
In between the trigger pin ringbolts, you may notice the sealing O-ring that is
seated in a groove in the launch tube, level with the nylon trigger plate.
Note the trigger rope handle: taken from one of the kid's toy spade.
Literally hundreds of launches without any problem.
The only thing that had to be replaced so far is the sealing O-ring.
This O-ring is seated into a groove, filed in the steel launch tube and seals the
rocket nozzle internally. This provides a perfect seal that allows pressurizing over
10 bar without any problem -- However: we always remain below 10 bar for safety reasons !
An exploding bottle is probably not a pretty sight.