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Homemade Stuff old and new
Homemade Water bottle rockets
1/20 of real speed !! rocket made by rasmus (400mS pr frame, realtime is 20mS pr frame)
1/5 of real speed, rocket made by pernille (100mS pr frame, realtime is 20mS pr frame)
So water rockets do take off, fast !!
The screws stops and hold the waterbottle when attached to the launcher
The bottle stopper plate
Main fixture made using 10 mm alu plates and 4mm screws
Quite big and solid construction is needed for safe opperation
The bottle is offcourse mounted with water inside, upside down
Then holder is carefully inserted
I made about 0.5 mm slip, the pressure will pull up the bottle !! and made it all fit hard
unpressured slip shown
valle parts screwed in, while heated up by soldering iron, this trick made it air tight too
valve on one side, release on other side, now like shown offcourse
Lets try to add a parashute and see if it work..
tiny 500mL coke bottle rocket, the fixture offcourse works with all bottles from the cocacola company, they all use exactly same measurements for the screw and holder area
My first water rocket, what a dumb idea to use cardboard !! not good when combined with water
Fins added, no big deal just glue them on as straight as you can see.
we found useable plastic in the bin
yay.. fins ready
eh, how much metal to add in the tip for good weight balance ?
I just use a few M8 screws and nuts
And use plenty of heatmelt glue
Rasmus : my first rocket ! see the nice soft tip, it will land nice and safe, at least that is the idea.
This one boys ! is a 2 liter monster rocket, wait and see
Making and flying water rockets is fun and safe for even small kids
Come on, we havent got all day.
Little sister perform final check on compression and energizer tool,
while big sister confirm water level is about 50% and ready for launch.
Great girls hold the release string, we are about to play.
pictures and a few videos from flights here:
THIS DESIGN DO NOT WORK AT ALL !!!
TOP WILL NOT FALL OFF, BOTH PARTS WILL STAY TOGETHER AND SHUTE WILL NOT BE RELEASED
metal rod come out of this hole
No fancy ways here
parachute cross type, wires are a bit of a pain, but we did not really see them tangled.
on top of the sero is a piece of cardboard, and a large spring to push out the shute.
a normal 35Mhz RC receiver is all we wanted to waste on this dumb simple project.
3 x AAA size alcaline cells, is perfect for power, note the on/off switch is just two wires to wrap a bit, here in off setting.
even the spring is homemade, welding wire
RED : the metal rod in hold position
BLUE : plastic with little hole for the rod
PURPLE : the plastic pieces are simply taped to the engine part of the rocket.
Power on, now we are ready
Nikolaj says ready for camera to be mounted...
videos from flight ONBOARD CAM:
videos from SAME flight ground cam:
Water rocket, radio controlled shute release
hi-speed water rockets takeoff
Water rocket 300km/t take off
From our hispeed videos and various tests, here are some data:
Take off speed at 2meters burnout = 83 meters pr sec = 300 km/hr
Time to reach 2 meters burnout = 0.06 sec
Acceleration: 110 to 140 G-force
Static thrust: 30-40 kg
weight of empty 1.5 L bottle: 42gr nothing added to it
Water fill ratio: 1/3 to 1/4
Air pressure used for our flights : 5-10 bars
max working pressure of soda bottles 10-20 bars
Burst pressure 40-60 bars
Release difficult with my launcher type at pressure over 10 bars
O-ring water tight issues at over 10 bars, maybe use two o-rings, and better fit.
Latest version launcher.
New and bigger and better o-rings !
DONE ! now stable and tight to at least 11 bars, but release gets difficult to pull out at 8-10 bars..