Introduction: Inclined Plane Timer

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This cylindrical timer rolls down the inclined plane very slowly, at a rate of 20cm per minute. It is inspired by traditional Inclined Plane Clocks and is very similar to the popular clock mechanism Tourbillon, except that in this case, the outer cylinder rotates instead of the inner clockworks (escapement).


  • 2mm tapping screws with various lengths
  • 52mm steel wire, diameter = 1.6mm
  • 15-16 steel balls, diameter = 11mm (pachinko balls)
  • Two rubber bands
  • Lubricants such as silicone grease or oil splay

You need tools of

  • Screw drivers
  • Drill bits
  • Files and/or sand papers

Step 1: Print Parts

Print all parts with supplied posture. No support structured needed.

Step 2: Clean the Printed Parts

The smoothness of the rotating parts is very important. Clean all the parts carefully.

  • Clean all holes with drill bits.
  • Make the all touching surfaces smooth, with files and sand papers.

Step 3: Assembly

Please take a look at the assembly guide video.

  • Use screws of appropriate length.

Step 4: Enjoy!

  • Prepare inclined plane and place the timer. Tune the angle of the plane to make the timer working properly.
  • The timer can be activated not only rotating the balance wheel but also swinging the outer case.
  • Racked gear (rail) is useful to avoid the slipping down.

Step 5: Learn


  • The cylinder (timer body) is kept stationary on the inclined plane by the weight. The center of gravity of the timer is always on the vertical line passing through the contact point to the inclined plane.
  • The position of the weight gradually goes down by the regulation of escapement, and the center of gravity moves to the right.
  • Then, the cylinder rotates clockwise and falls down a bit. With this motion, the position of the weight is raised, and the escapement gains additional energy to drive.

Inclined Plane Clocks

  • You can find antique clocks using same principle. Typically they work for a week on a single inclined plane.
  • Using 3D printers, it is difficult to make practical clocks from the viewpoint of duration and accuracy.


  • Tourbillon is a popular mechanism of a premium mechanical watches. The escapement is rotated to avoid the degradation of accuracy caused by the posture variations.
  • This timer has a mechanism similar to the tourbillon. Instead of rotating escapement, the outer shell (cylinder) rotates. The posture of the central escapement unit is kept by the weight and gravity.