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Balloon powered hovercraft

Balloon-Powered Hovercraft

Grab a few household items and build your own balloon-powered hovercraft – just one tap sends it flying. You can also make it your own by adding some Wallace & Gromit cut outs which you can download from our website.

Instructions below

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This kit requires the use of sharp objects and electric tools, always be careful!

Download kit Instructions and extra parts to make your kit look great! PrintPrint these instructions and get making!
  1. Make a hole in the side of a bottle top

    Check you have all the required items listed in the ingredients box above.

    1Make a hole in the side of a bottle top

    Make a hole in the side of a bottle top and push the tube through.

  2. Hot glue the inside of the hole

    2Hot-glue the inside of the hole

    Hot-glue the inside of the hole – but don't block the end of the tube. When the glue is nearly set, try blowing through the tube to check it's clear.

  3. Hot glue the gap between the hole and the tube

    3Hot-glue the gap between the hole and the tube

    Hot-glue the gap between the hole and the tube. This needs to be airtight, so add glue around the hole.

  4. Glue the other bottle top to the CD

    4Hot-glue the other bottle top upside down to the CD

    Hot-glue the other bottle top upside down to the CD. Try to make it as central and upright as you can. It must be airtight, so add more glue if you need to.

  5. Glue the two bottle tops back to back

    5Now hot-glue the two bottle tops back-to-back as shown

    Now hot-glue the two bottle tops back-to-back as shown. Again, you need an airtight seal.

  6. 6Test that your contraption is airtight

    Test that your contraption is airtight and the valves work. Close both valves and blow into the tube. If you can hear air escaping, find the hole and patch it up.

  7. Bend the paper clip

    7Slide the paperclip onto the tube

    Slide the paperclip onto the tube. Hold it with a pair of pliers as shown and bend the bigger loop downwards.

  8. Slide the paperclip onto the tube

    8Snip the extra loop off the paper clip

  9. Push the other end of the tube through the paperclip

    9Push the paperclip further onto the tube

    Push the paperclip further onto the tube and loop the other end through it. This should temporarily seal the tube. Now test it by closing the bottom valve, opening the top one and blowing into it. If you hear air escaping, adjust it until it seals properly. The tube needs a sharp kink in the corner to seal.

  10. Put a balloon on the top

    10All working?

    All working? Good. Add the balloon on top.

  11. Decorations

    11Time for decoration!

    Time for decoration! Cut out and colour in the printed parts and cut slots where indicated in the base.

  12. 12Fold Wallace and Gromit's tabs backwards

    Fold Wallace and Gromit's tabs backwards, and pinch-fold along the dotted line. This should keep them upright when glued in.

  13. The finished hovercraft

    13Spread a little glue on the CD

    Spread a little glue on the CD. Insert Wallace and Gromit through the slots and press everything down. Let it all dry. Make sure nothing hangs over the edge.

Balloon powered hovercraft

Let's play!

  • Close the bottom valve, open the top valve and release the tube from the paper clip holder.
  • Blow into the tube to inflate the balloon. When it's fully inflated, close the top valve.
  • Close off the tube by tucking it back into the clip.
  • Open the bottom valve. You can adjust this for more or less airflow. Start off with plenty. The balloon will go down fast, but everything should work!
  • Place your contraption on a smooth surface and fully open the top valve. Let go and your hovercraft should float around!
  • To try again, simply close the bottom valve and re-inflate the balloon.

Lets experiment!

  • How much airflow does your hovercraft need to work properly?
  • How long can you make it run for?
  • Try adding a little weight. Coins work well. How much can your craft carry before it stops?
  • Try different surfaces. Can you make it work on lino? How about a wooden surface? Try it down a slope! With lots of airflow it might even work on smooth paving stones – give it a go!
  • Try leaving the inflation tube open. You'll need lots of airflow to create lift as most of the pressure will leak away. You should find it propels itself along for a few seconds!
Build more great contraptions
Time
45 minutes
Difficulty
Medium

Parental supervision required

Ingredients

Things you'll need to make this

  • An old CD or CD-R

    You can use the protective plastic disk that comes in most CD cases too, but make sure it's the stiff kind.

  • Two sports-bottle tops

    The type that you lift up to drink – get two identical ones.

  • Silicon tube

    Approximately 15 cm. Most pet shops stock it in aquarium supplies, or you could try a DIY store.

  • Paper clip

  • Printed parts sheet

  • A balloon!

Download instructions

You'll also need these tools too:

  • Hot-glue gun and glue sticks
  • Sharp craft knife
  • Scissors
  • Drill or electric screwdriver with drill bits
  • Pliers

Competition

Build your contraption to wake up Wallace

Win a starring role in a future
Aardman animated production

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