The Solar GraviTrack Marble Machine Kit is our newest addition to the Marble-Drop mechanism family. The Solar version pulse-moves the elegant hand-off mechanism that passes marbles to the top of a sweeping multi-level track. You will witness the fascinating step-by-step action of the arms as the geometry changes periodically. Patience is rewarded with the plunk, and rollll of a successful motion cycle. The more light it gets, the more often it moves. It's solar-powered stop-action motion!

You can now solder your own, or choose a solder free version.