Intro: Launch It! Contest Entry: the Alcohol Fueled Soda Bottle Rocket
Step 1: Getting Started
So anyway, this rocket is a load of fun, first I'll show you the vids (start with the one on the top and work down) and then I'll give instuctions.
Step 2: Materials and Supplies
Right, the stuff you'll need to the build the rocket are:
1 clean 2liter soda bottle with lid (duh)
1 sonic screwdriver or other device to create hole in lid
2 bamboo barbecue skewers
4X2 strip of 2D adhesive material, or clear packing tape
1 pair of hands or more connected to a brain
Stuff to fly the rocket:
Safety equipment, safety glasses and gloves
Alcohol (isopropyl or rubbing, the type you get a pharmacy, not the liquer store), and other liquids (you'll see soon)
Long handled ignition deice, such as a lighter
Due to concerns about safety;
Two long drinking straws
Sheet of cardstock
All of this stuff, except for the sonic screwdriver, can be found around the house, however if you do have sonic screwdrivers lying around your house, let me know.
Step 3: Building the Darn Thing
Right, as demonstrated in the video/s, you have to make a hole in the lid/cap/nozzle wanabe, so whip out your handy dandy sonic screwdriver or equivelant and create a hole about 1cm in diameter in the middle of said lid/cap/nozzle wanabe. Size of hole will affect to some degree rocket performance, too small, won't burn right, to large, not as much thrust.
Then tape the skewers onto the side of the bottle, as seen in video and pictures (note, in the video and instructions, I use clear packing tape, in the pictures I'm using masking tape for clarity purposes only, it's rather heavy for use on our little rocket).
There were some concerns about the safety of the skewers afixed to the rocket, and of stability, so here's some alternative designs.
Instead of skewers taped to the sides, tape two straws on in exactly the same manner as the skewers. I would recommend using straws from Burger King, they are thicker than most other straws. If desired, fins can also be added to the rocket, two triangles of cardstock can be bent into a V and tped onto the skewers. It may be neccisary to shape them to allow the ends of the skewers be inserted into the ground and angled. I wouldn't recommend using fins when fueled with just alchol, the slight improvement in predictability of flight path doesn't justify the significant reduction in altitude (from 30-40 ft to 15ft). However on a higher powered version (youl find out later) it would probobly be worth it.
Congratulations, youv'e just completed the construction of your own flight ready rocket, and that took what, 3 minutes tops?
Step 4: Takeoff! WWWHHHHOOOOOOOOOO!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Right, to fly the rocket, gather the materials described earlier and go back to the first step and watch the videos again. Then come back here. Right, what you need to do is go outside to obstruction-free area. Then dribble 5-10 (amunt of fuel will vary with grade of alcohol, I can fly on 5 drops 99%, but 10 are needed for 76%) largeish drops of alcohol into the rocket. If you haven't already screw on the nozzle. Place your finger or a piece of tape over the hole and roll the acohol around inside for about 30-45 seconds to allow it to evaporate.
Don your safety equipment and move everbody and any flammables away from a patch on the ground that you dont mind lightly scorching.
More on safety:
This rocket emits flaming vapors and hot gases, sends hot plastic flying erraticly through the air, and your dealing with intoxicating flammable liquids, please use that underdeveloped organ stored away in your skull, and exercise caution.
Insert the ends of the rockets launch guidance rods/skewers into the ground at a slight angle unill it is stable. Perform countdown, and when ready to launch remove your finger/tape from nozzle, and at arms length with apply igntion source slightly below (1cm) the nozzle opening. With a whuoosh your rocket will leap forth into the heavens about 20-30 feet and tumble back down to the ground.
If you are using straws instead of skewers, still insert your skewers into the ground as described above and then slide the straws taped to the rocket over them, creating a mini launch tower.
To re-launch, allow the rocket to air out for a minute or so and repeat steps on this page. your rocket will survive 5-7 flights before it will suffer structural failure and melt. At that point you should save your nozzle/cap and make another, using the salvaged nozzle.
Pics coming soon
Step 5: Science Scoop, Further Instructables, and Dedication
Right, whats going on here is that we are creating a fuel/air mixture inside of a semi-confined space, igniting it, and derecting the fow of hot gases to create thrust which is directed downward to create lift.
This idea is completely my own, I was unaware of other people coming up with this idea until viewing that other instructable.
This would probobly make a great science fair experiment, you can fiddle around with the amount of fuel used and the type to. Once I used a mix of alcohol and hydrogen peroxide to create my own V2. It flew much higher, with a much louder wuff, and completly melted a brand new rocket, I don't recommend trying it until you gain lots of experience with just alcohol. I would really like to try this with a single drop of ether, however it's dashed difficult to obtain the stuff.
Other fuels to try are:
Butane (allow the rocket to fill up with gas from a lighter)
Very small amounts of acetylene
When experimenting with new fuels, I recomend you find a way to light the rocket from a distance, such as a model rocket igniter
For more on the science of burning vapors and fuels, see Kiteman's Instructable Be an Aeronautical Scientist: Make Your Own Jet Jar For a Few Pennies. How noble of me, I'm actually linking to my prime competition's Instructable.
Remeber, if you like this Instructable, rate me rate me rate me (please please please)!
I would like to dedicate this Instructable to Cdr. William C. McCool, pilot of the Space Shuttle Columbia, the man who told me to follow my dreams, and fanned the flame in me to be an astronaut.
Live long and prosper