“I sell what all the world desires: power.” So said Birmingham’s Matthew Boulton when he partnered with James Watt to make the world’s first powerful industrial engines. They were actually 'vacuum engines', with vacuum from condensing steam on one side of their pistons and atmospheric pressure on the other side. Here’s how to make a big working model of those pioneer engines, using a bike wheel, plastic plumbing and vacuum cleaner power instead of steam.
Boulton and Watt’s enormous steam engines had a piston in a cylinder, pulling and pushing the flywheel via a crankpin and a valve to turn the vacuum on only when the piston is being sucked down and not otherwise. The valve needs to move with a quarter-turn lag after the piston.
A front bike wheel makes a good flywheel since it has ball bearings. The crankpin can be a long thin bolt through the spokes, positioned about 30mm from the axle. You’ll need some plastic (polypropylene) plumbing, with...