A clockwork/dynamo driven model hacksaw.
This model was built with some of my oldest Meccano and represents a typical scruffy overworked workshop power hacksaw. Fitted with a Junior Hacksaw blade it actually works but would not break any records for cutting metal quickly!
It is powered by a tiny realistic 1.5V motor I have connected to the dynamo of an old clockwork radio. This dynamo is driven by a Meccano clockwork motor and operates the hacksaw model well. Interestingly, reversing the clockwork motor reverses the hacksaw model’s motor as well.