This is my first instructable so i hope you like it. I have been making these rockets for about 4 years and nothing else compares to amount of fun you can have for it being so easy. I will show you how to make the basic rocket and from there you can experiment with it, i have put these on boats and cars with surprising results.
Step 1: Gather Your Materials
All you will need for this instructable is
-1 soda bottle(with cap)
-a used toilet paper roll
-safety goggles(not shown)
-grill lighter(not shown)
Step 2: Rocket Nozzle
What you will need to do is CAREFULLY round out a hole in the center of the soda bottle cap(you could use a drill for this).You want your hole to be about 1/4in or so.This is one of the things you might want to play around with after you have finished, the size of the hole will effect the performance of your rocket.
Step 3: Launching Platform
For this step you will need to take your toilet paper roll and cut out a hole about 3/4in sq. The hole should be about 1/3 of the way from the top of the roll.
Step 4: Fueling and Launching
Now that you rocket is complete its time to fuel it up and launch it off. To fuel your rocket you need to pour just enough rubbing alcohol into your soda bottle so that it covers all the sides but you do not want a pool of alcohol in the bottom, now screw on the cap and set the bottle upside down like in the picture and your ready for liftoff. When your ready to launch, put on your safety goggles, hold the grill lighter up to the hole and let a little gas flow in before lighting the lighter then light the lighter and WOOOSSSSSHHHH!!!! we have liftoff. Now that you have a working rocket you can add fins a nosecone or whatever you please, you can vary the size of the nozzle and the amount of fuel, the max height i have gotten with one of these rockets is a little over 20ft. I hope you enjoyed my first instructables, please leave comments and vote for me in the Launch It challenge. -Sorry about the video quality and please be very careful wile i have never been hurt of had any accidents with these, it's always possible.
-you can use a 2ltr bottle with the same cap and launching procedure but you will defiantly want to do this outside for they are alot more powerful, i have had 2ltr bottles go up to 40+ feet
-for ignition you can use a piezo igniter from a grill and add a length of wire to it and set the wire just inside the cap