How to build a stomp rocket
Make a rocket that will take to the sky with a stamp of your foot!
If you’re under 18, make sure you have an adult with you.
1. Make the pump
To create lift in our rocket we’re going to need some air. Start with a two-litre drinks bottle and a short piece of hose less than one metre in length. Wrap some foam tape around one end of the hose until it fits snugly into the neck of the bottle, then secure it with duct tape. Make sure it’s attached really tightly, ensuring that no air can escape through the gaps.
2. Start your launchpad
Next, you need to create a launchpad. Put some pebbles or stones into the bottom of a four-pint milk bottle to weigh it down and carefully cut a hole near the bottom below the handle. Feed the free end of the hose up through the hole and out of the top of the bottle. This will be where the air shoots out and pushes your rocket into the sky.
3. Finalise the launchpad
Next you will need some plastic tubing around two to three centimetres in diameter – you can get it from a hardware shop. Ask an adult to saw off the end until you have a piece around 20cm long, then smooth the end down. Draw around the tub on the lid of the milk bottle and cut a hole in the lid so that the tubing will fit tightly inside.
4. Create your rocket
Next, cut a square of thin card around 16cm wide and long, then wrap it around the plastic tubing. Put sticky tape around it like you can see in the image above, making sure there are no gaps. Cut a circle of card out and stick that tightly over the end of the tube. Your tube should be quite a tight fit on the plastic tubing but should come off easily when you blow into it.
5. Ready to launch!
The final step is to put some foam tape on the other end of the hose so that the plastic tubing fits tightly on top, then secure it with duct tape. Put the milk bottle back together, then place your cardboard tube over the plastic tubing and jump on the plastic bottle! Your rocket should shoot into the sky as air is pushed out of the bottle and into the tube.
The air inside the bottle is pushed down the hose and into the plastic tubing, and as the pressure quickly builds the air will shoot upwards towards the rocket, forcing it skyward. You could also try adding a cone to the top of your rocket and fins on the side to make it more streamlined.
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