A K’NEX ball machine is a moving structure built from K’NEX that lifts balls to the top, then guides them through tracks, obstacles, and tricks on the way down. It is part engineering, part art.
The idea first appeared in 1995 with the release of the K’NEX Big Ball Factory. This was one of the most complex and popular sets ever made. It included more than 3,000 pieces and featured working lifts, branching paths, and moving components. It was designed to show the full creative potential of the K’NEX building system.
Since then, ball machines have become a popular project for builders of all ages. Some recreate the original Big Ball Factory. Others design their own machines with unique layouts, mechanisms, and features. Most builds are powered by motors and use gravity to move the balls through a series of custom-built tracks.
These machines are a mix of mechanical skill and creative design. They are still being built and shared by a strong online community through videos, tutorials, and part guides.
How it works
- A motor or hand crank powers a lift.
- Balls are raised to the top.
- Gravity takes over — the ball travels down a network of tracks.
- Switches, funnels, jumps, and loops make each path different.
Why people build them
- They’re fun.
- They teach mechanical design and problem-solving.
- They’re fully customisable — no two builds are the same.
Build your own
You don’t need a full kit. Most builders start with spare parts and follow free guides online. One of the most iconic examples is the original K’NEX Big Ball Factory.
➡️ View the Big Ball Factory instructions here
Start small — one lift, one path — then expand.
