This gimbal uses parts salvaged from a BIC pencil to enable smooth rotational motion. An M3 clearance hole is provided in the centre ring for hanging a weight. When weighted, the centre ring will maintain itself parallel to the ground, even as the outer ring rotates. The pivots are so smooth, even very light weights work!

A single BIC pencil can be used to create two types of pivots - one using the inner and outer tubes, and another using the components from the nose mechanism. 

The gimbal parts can be printed without support. Cut off the tip of a BIC pencil as shown in the photos above. Each ring has four holes - two sized for the black barrel piece, and two sized for the nose axle piece. Simply press-fit the piece into one set of holes, and mate them together with the corresponding piece in the larger ring. You may wish to warm the printed part before press-fitting.

Originally posted on my blog. If you liked this model, check out my Marble Balance Maze model available for download!