This instructable will give you an isight on how to create a 2 liter soda bottle rocket. This rocket uses a lot of common or cheap priced materials and is easy to construct. This rocket will fly high and definitely put a smile on your face. Follow these simple instructions and have fun!
By: Haley and Anna
Step 1: Materials
Step one is the simplest step, gather all the desired materials. You will need:
3- 2 liter soda bottles with labels removed
1- 4"x 7" piece of cardboard
1- pair of scissors
1- sheet of painter's drop cloth
1- tennis ball
1- hot plate
1 liter of water
a ball of string
and a pressure launcher
Step 2: Cutting the Fins
Place one soda bottle aside, you will need the entire bottle because that will be used as the body of your rocket. Next you need to cut the fins. The size that we found to work best was 5.5 x 2.5 inch parallelogram shaped fins. You will cut three of these and tape them equi-distant to each other with duct tape on the set aside bottle.
Step 3: Making the Body of the Rocket
Okay, you are about 1/3 of the way done. This step is constructing the body of the rocket. You will need your last two soda bottles. Take one and cut the bottom and top off so that it is an open cylinder. This will be used to connect the rocket to the parachute so you can duct tape one of the ends to the top of the rocket.
Step 4: Making the Top of the Rocket
You are going to need to alter the last bottle you have. Before you cut or do anything to it, the top needs to be melted. Take out your hot plate and place the bottom of the rocket over the hot plate (the bottle should be parallel to the hot plate, not perpendicular) and slowly spin it. Within a few minutes the once bumpy bottom should be smooth and a bit pointed.
Once the bottom is done, you need to cut the top off the rocket leaving close to 11" left. Next you will cut three 2" deep x 1" wide slits in the top of the rocket. This should leave you with the area where the cap of the soda bottle was fully open with 3 slits in it. Bend those slits back so they point out, these slits are what will lift the top off of your rocket and release the parachute.
Step 5: The Parachute
Next is the parachute. This is what the painter's drop cloth is used for. First, fold the drop cloth into a square and then cut it. Once it's in a square you want to fold the drop cloth in half, and then in half again about 3 more times. It should look a bit like a long triangle at this point. Cut about a foot off only on the bottom (NOT the pointed top). Unfold it and it should look like a circle. Keep re-folding and cutting until the diameter is about 54". This seemed to be the perfect size for a parachute. After you have reached the desired size, place little squares of tape on the ends of the parachute 8 times. Punch holes and then tie 54" strings in each hole. This is your parachute.
Step 6: Putting Everything Together
Once you have the string tied to the parachute you are going to need to string it through the tennis ball. Cut two slits, one right above the other, in the tennis ball and string the string through. This will take some time and you may need tweezers to help you pull the string through but once all 8 strings are through, tie a big knot at the end to ensure none of the strings will slip through the tennis ball and ruin the parachute's descend. Another good trick to almost guarantee the parachute releasing is to lightly cover the drop cloth with baby powder.
Step 7: Continued..
Now, to fold the parachute the right way is fairly simple, you just need to keep folding it in half, but each time you fold it press down and push all the air out so it is as compact as it can be. Once you can't fold it in half anymore and it's become really skinny, fold the pointed top in and do that once more leaving the bottom where the string is connected free from being folded into anything (the air will need to get in easily to make it open up). Now that it is really small you can place the parachute in the melted bottle, place the melted bottle inside the attached second bottle while leaving the tabs you cut out. The tennis ball and extra string should easily fit in the middle section of the rocket with the top filled by the parachute.
Step 8: The Launch!
Now that everything is together and looks like the intro picture you are ready to launch! Fill the bottom part of the rocket (the area with the fins and nose cap) with 1 liter of water. Next you will hook it up to a pressure launcher and after a few pumps you can pull the string and watch your rocket soar up! We can't guarantee enormous heights but your rocket will definitely go high and with the right wind, last for close to 30 seconds in the air!