Frictionless CD & Balloon Air-Cushion Hovercraft
Zero-Friction Gliding on an Escaping Micro Air-Bearing
Household Scraps & Tools Needed
Assembly Instructions (5 Steps)
Follow each step carefully. Work together to clean waste, score precise cuts, align pivots, and test kinetic mechanics.
Clean & Prep the Compact Disc Base
Wipe the shiny bottom of the old CD clean of dust and fingerprints. The smoother the bottom surface, the better the air cushion forms.
Glue Pop-Top Cap Over Center Hole
Apply a generous bead of hot glue around the base of the sports pop-top cap. Press it firmly over the center hole of the CD on the printed side, making an airtight seal.
Push Cap Closed & Stretch Balloon
Push the sports valve down into the closed position. Stretch the neck of a balloon over the top collar of the cap without tearing the rubber.
Inflate the Balloon from the Underside
Blow through the bottom center hole of the CD to inflate the balloon to full size. Pinch the balloon neck or pull the pop-top valve open.
Open Valve, Place on Floor & Glide
Pull the sports cap open and set the CD on a smooth floor or table. Watch it rise slightly on an invisible cushion of air and glide effortlessly with a light touch!
Fluid Air Bearings & Friction Elimination
Air escaping through the CD center hole spreads underneath the disc, creating a thin pressurized air cushion (air bearing). This separates the CD from the table, reducing friction nearly to zero.
Without friction opposing motion, a tiny finger tap sends the hovercraft gliding effortlessly across entire rooms in a straight line.
Skills Your Child Develops with This Project
Friction & Surface Drag Concepts
Comparing motion with and without air cushion activation on various floor textures.
Airtight Craft Construction
Creating a continuous leak-free glue seal around the bottle cap flange.
Inertia & Momentum Observation
Observing how uninhibited momentum preserves linear speed and direction.
Fun Family Experiments & Mini-Games
Tabletop Hovercraft Air Hockey
Set up two books as goalposts on opposite ends of a smooth dining table and play 1-on-1 hovercraft air hockey.
The Surface Glide Comparison
Test glide distances on polished hardwood, kitchen tile, smooth paper, and short-pile carpet to chart surface friction differences.
Parent Note:
A 5-minute build that delivers pure science excitement. Children are fascinated by how a simple puff of air completely eliminates friction.
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