Hyunjidesign

I designed and 3D printed this fun and silly hand-powered marble machine that cycles marbles around through several mechanisms. Inspiration for this project comes from marble machines that have been developed by many, including Mechanical Kits and Mr. H2. My marble machine is in three sections – climbing steps, falling rails, and revolving ferris wheel. The marble output from each section becomes the input of the next, leading to a continuous motion of the marbles around the machine.

Section 1 – Climbing Steps

The climbing steps are composed of 6 steps, 6 cams, a shaft, and a gear. As I turn the gear by the extruded handle, the shaft and the cams rotate. The cams on the shaft are oriented in a way that moves adjacent steps in opposite directions. The highest point of one step becomes lower than the adjacent step after 180 degrees of rotation, resulting in the marble moving up 1 step every half turn. Each step has an inward slope on the top face to drive the motion of the marble in the correct direction, towards the higher step. The hexagonal fit between the cams and the shaft enable strong torque transmission. 

Section 2 – Falling Rails

The falling rails section is composed of 4 zig-zagging rails and a curved base path. The marble is passed down from the top step of the climbing steps, falls down the rails, travels through the curved path, and exits at the start of the next section – the revolving ferris wheel.

Section 3 – Revolving Ferris Wheel

In the revolving ferris wheel, the marble enters from the bottom of the ferris wheel gear, where it exits the falling rails section. The ferris wheel gear rotates from its gear connection to the shaft gear in the climbing steps section. After the marble travels 180 degrees in the ferris wheel, it rolls out on top and rolls to the bottom of the climbing steps on the connecting rail. The holes in the ferris wheel gear are sloped so that it forms a positive angle when the hole is at the bottom, and a negative angle when it is at the top – the marble gets drawn into the wheel at the bottom and gets rolled out when the marble is at the top.