Snake-in-the-Grass Animatron

This simple snake animatron lets you build your own snake however long you like (well, within reason) and using whatever colors you like. It uses a serpentine path filled with 6mm diameter Airsoft BBs to propel your snake around the circuit. Each snake segment is independent, with a little tab that fits down between the balls which allows you to put the segments anywhere you like. The balls are pushed around by the dial, which is, essentially, the inner race of a partial ball bearing.

The included 3MF file includes seam painting to keep the seams out of critical portions of the track, and also has supports painted for the head to support the chin and tongue. For the snake, just print one head, one tail, and as many intermediate sections as you like in whatever colors you like.

Assembly

You will need about 145 6mm diameter Airsoft BBs. First fill the track, except for the part with the dial with BBs. Place the dial in the remaining circular pocket and align the notch in the edge of the dial with the notch in the ball groove. Push additional balls through the gap formed by the notches to almost completely fill the remaining space in the ball track. You will need to be about 3 balls shy of a full track because each snake segment you insert requires a little bit of space. Give the dial a spin to make sure the balls circulate freely. Note that the balls are just driven by friction, so you need a little downward pressure on the dial the get the balls moving.

Next, for each snake segment (including the head and tail), you will need  to press in one of the little tab pieces as shown in the photo above. The tabs should stay put when pressed in place, but if not, you can use a tiny drop of superglue.

Next, you can insert the grass pieces into the slots in the field. To keep them in place first put a little bend into them as shown above, then insert into the slots. Finally, I recommend putting adhesive rubber feet on the bottom to keep it from sliding around as you turn the crank.

Now you can start inserting your snake segments into the ball track. There should be exactly 3 balls between the tabs of adjacent snake segments.

Design by LoboCNC on MakerWorld (license: BY-SA).