ACADEMY 18174 Da Vinci Series Rolling Ball Timer Mechanical Model Kit HO PC Parts Truck: Tangent 70-Ton Gould Caboose

Truck: Tangent 70-Ton Gould Caboose Roller Bearing

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Perfectly sized for smaller layouts

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ACADEMY 18174 Da Vinci Series Rolling Ball Timer Mechanical Model Kit HO PC Parts Truck: Tangent 70-Ton Gould CabooseACADEMY 18174 Da Vinci Series Rolling Ball Timer Mechanical Model Kit The Da Vinci Rolling Ball Timer kit was inspired by a sketch of an escapement mechanism drawn by Leonardo da Vinci. Using the laws of motion and the concepts of gravity and kinetics to measure the passage of time. The mechanism employs precision gears to power a moving platform which in turn propels a rolling ball. Timing speed is controlled by adjusting the weight and balance of