This is a simple model of two Meccano men — a teacher writing on a blackboard, and a man lifting weights.
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Teacher and weightlifter
The mechanism is driven by an electric motor, geared down using two sets of worm gears and pinions, driving a shaft which runs the length of the model. At each end of the shaft is a bush wheel with an eccentric bolt. One end of a piece of thin wire is secured to this bolt and the other end is secured to one of the arms.
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The mechanism
Modernised version
The ‘modern’ version of this model has a whiteboard rather than a blackboard since these are no longer used in schools!
It uses repainted parts, a simplified mechanism utilising a geared electric motor, and a ‘box’ constructed from all Meccano parts.
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A modernised version of the teacher and weightlifter