Step 1: What You Need.
2- 3" PVC pipe 15" long
3- 3" PVC Clean outs with caps
1- 1/2 12" long plastic threaded pipe
1- 3" PVC pipe cap
1- 3" PVC pipe coupler
1- 2" PVC 90 degree
1- 14" piece of 1/4" copper tubing
1- primer bulb
1- on / off / on momentary switch or off / on momentary if you use a piezo igniter.
1- coil , condenser , relay or piezo igniter.
1- 12 volt portable air compressor
1- can PVC glue
1- roll solder
1- small tank for gas 1/2 to 2 oz
1- small one way valve
1- pressure gauge minimum 50 PSI (air pump may include gauge and air T ) .
1- air T
1- 4 feet tubing 3/8 OD 1/4 ID for air
1- 4 foot small gas tubing that will fit in the big tubing , the smaller the better.
1- 4 foot spark plug wire
1 7.2 to 12 volt stick pack battery, available at hobby shops.
Step 2: Introduction to Assembly
If you decide to build this project you may need to improvise on various parts and construction.
All the parts I used may not be available to you, or you may have a better idea about how to construct this project . Either way , you need some building skills and good old fashioned rigging. good luck.
WARNING :this project has the potential to be dangerous as you will be igniting compressed gasoline vapor and using a high voltage coil which could result in shock. If you make this gas powered soda bottle rocket, please use your head ,wear safety glasses and protect your hearing.
I have shot the rockets for years and have yet to get hurt, but if you're careless , someone could easily get hurt.
Step 3: Construction: Step 1
Make sure they're pressed on all the way.
DO NOT glue the other caps on yet.
Step 4: 2
Make sure the fittings are lined up and you don't drill where the caps thread in.
Bolt the two sides; together finger tight , you will have to loosen it later.
Step 5: 3
After the framing is done, bolt or screw the bottom cap on.
Do Not Glue The Cap - You may need to fix it later.
Step 6: 4
After the hole is drilled, glue the elbow pipe in.
Step 7: 5
Step 8: 6
Step 9: 7
You will need a coil that will fit in the PVC pipe; a motorcycle coil will work best.
Step 10: 8
Step 11: 9
If you're using a piezo igniter you don't use a relay.
The relay is used to make continuous spark.
Step 12: 10
If your using a piezo igniter drill a another hole for it.
Make sure you have room in the pipe where you're drilling.
Step 13: 11
I used a small 1/2 oz car vacuum chamber.
1/2 oz will give you about 40 to 50 shots.
Step 14: 12
Remember you have to fit a battery in later.
You should have your coil and air compressor wiring coming out the back of the bottom PVC pipe.
Depending upon where your fuel tank is mounted now might be a good time to install it. Make sure you have a way to fill it.
Step 15: 13
It may be easier to wire up the switch before installing it. The same goes for the gauge and primer bulb.
Step 16: 14
The main goal is to run the fuel and the ground line through the air line to the launcher.
Make sure you run the ground, fuel and air line 3 feet.
One end of the tee goes to the gauge the other two go to the pump and launcher.
Note: go heavy on the super glue!
Step 17: 15
The other line is for filling the gas tank.
Step 18: 16
Connect the one way valve to the fuel line entering the air line. The other end goes to the primer bulb output.
The primer bulb input comes from the bottom of the gas tank.
All the grounds and negatives are shared.
Leave room for the battery.
Step 19: 17
You can solder a barb fitting on the copper pipe for the hose, but keep the length at 12.5 "
Solder the igniter end closed (refer to chart 2). Put a small pin hole in the copper tubing right below the solder.
The black mark is how far the fuel line comes up in the copper air line.
Step 20: 18
Make sure it is centered, then glue it.
Step 21: 19
Run the fuel line up through the copper tube about 2.5 " from the top.
Connect the air line to the bottom of the copper tube. You have to cut some of the air line to do this (refer to chart 2.)
Cut the ground line the same length as the air line. Splice the wire and connect it to the copper tube.
Run the spark plug wire along the copper tube stopping about 1 1/4 " from the top
Glue the spark plug wire to the copper tube. Insert a piece of piano wire in the center of the spark plug wire sticking out about 1 1/4 " . Put a small bend at the top towards the copper tube. After all measurements are made, glue the air line to the copper tube with super glue.
Step 22: 20
The copper pipe should stick out about 1/2 "
Fill the end with hot glue.
Step 23: 21
Step 24: 22
Step 25: 23 IMPORTANT !!!
If the bottle is too tight it may explode when fired. If the bottle does explode, most of the time, it just blows the front of the bottle off with a loud bang. If it fails to fire DO NOT GET IN FRONT OF THE BARREL. Wait a few minutes and unscrew the back and remove the bottle.
Step 26: Fire !
1. Make sure there is no bottle on the launcher.
2. Fill the gas tank by turning it up side down putting the filling hose in gas and pumping the
primer bulb until all the air is out of the line and gas starts to run out of the copper tube.
3. Make sure you don't have a bottle on the launcher.
4. Run the air pump to expel any excess gas from the vaporizer assembly.
5. Now you can put the bottle on the launch tube and press down until it hits the stopper.
6. Press the primer bulb 1/2 pump you should see the fuel run into the vaporizer tubes.
7. Turn the compressor on and pressurize the bottle
to 25-35 psi.
8. Any higher is at your own risk.
10. Repeat 4-7
11. IF it does not fire, don't get in front of the
launcher. Wait a few minutes, then unscrew the launch
tube and remove and replace the bottle
(the bottle may be flooded)
Try putting a few ounces of water in the bottle, this will give you a nice boost.
You can also shoot this from the hip if you feel confident enough after a few firings,
I don't however advise shooting from your shoulder unless you devise some facial
Shielding, or other protection.
Step 27: Tray
You have to make a launching tray out of another soda bottle just chop the bottom off about 1/4 up.
You can also put water in the rocket bottle (about 1/4 full) for some extra kick.
Do not fire objects over 6 oz.
Wear safety glasses and ear plugs.
And Most Of All Use Your Head!!
Think about where you are and who is around when you decide to start firing!!!