Water Rocket Instructions
Tools Needed:
- Scissors
- Duct Tape
- Box cutter or Razor knife
- (Not Needed but helpful) - super ball, or suitable weight.
- 3-4 plastic soda bottles (2 liter size)
Preparation:
Wash out the bottles to that you do not have to deal with the soda making everything a sticky mess.
Take one of the bottles to act as your base of your rocket. Look around the opening where the cap screws off to see if there is still a plastic ring on the bottle left behind that was used to seal the cap on when you bought it.
You will need to cut this ring off of the bottle before you place it on the launcher. Failure to remove the seal ring can cause problems with the launcher.
Body Construction:
Take the bottle that you selected as the base and set it aside for a moment. Take one of your other bottles to use to extend the rocket body. You will want to draw a line around the bottle where the spout end meets the body of the bottle. You can use two pieces of notebook paper taped together as a guide for drawing the line.
Cut along the line to remove the top.
Take the bottle that you are going to use as the base and turn it upside down, and take the bottle that you just cut the top off of and mate those two together.
Make sure that they are aligned as straight as possible.
Tape these bottles at the joint securely with a couple of wraps of tape. Tape the two bottles together as shown below.
Take a third bottle and cut the top and bottom off.
Cut the middle piece once lengthwise to make a shroud to wrap around the taped body to make sure the two body pieces will not come apart.
Wrap the shroud around the two bottles. Center the joint of the two bottles within the shroud and tape the shroud securely into place.
Take the bottle top that you cut off the bottle and place it on the exposed bottle bottom (which will become the top of the rocket.)
Tape the nose cone on securely. After the nose cone is mounted on the body should look like the picture below.
You will need some type of weight to attach to the nose cone of the rocket. This can best be accomplished by using a golf ball sized super ball. Please do not use a golf ball. Tape the ball on to the nose cone (bottle spout).
The completed rocket body with weight should look something like this:
Fins Construction:
Fins are constructed to give the rocket Stability in flight. Without fins your bottle is going to take on the flight characteristics of a balloon that you blow up and let go. My advice at that point is to duck :-). Follow these steps to build and mount fins:
Take a 2 liter bottle and cut it apart just like you did when you made the shroud. (Cut the top and bottom off.) Take the section that like you used for the shroud and cut it into three 6" long x 3" wide strips. Take one of these strips and fold it in half to where you will have about a 3" x 3" square. From the open end of the fold measure back about 1/2" on each side and fold back again to where your fin looks like this:
Repeat this for the other two fins. If you have been using a clear packing tape, (up to this point,) you will want to use duct tape on the fins. Use the duct tape to wrap the fins so they will be rigid and will hold up during flight. Do not tape the folded back 1/2" tabs.
The exposed, un-taped 1/2" tabs that you folded back are how you will tape the fins to the rocket. Tape the fins onto the rocket body by butting them against the body, spaced equally around, as illustrated below.
Place tape lengthwise on each side of a fin to attach it to the body, allowing a little tape to extend in either direction. Then apply tape across the initial tape for additional strength. (See the pattern below.)
Have fun and make sure no one is standing under a rocket which is returning to earth from flight. The weight attached to the nosecone and the velocity of the returning rocket are enough to cause serious injury.