“One form of intermediate technology employed in my shop, the human-powered machine, provides an alternative to both the hand tool and the power tool. At this time, my tools in this category include a treadle-powered bandsaw, a hand-cranked drill press, a pedal bench grinder, and treadle metal lathe. The lathe and drill press are more than 100 years old and were manufactured to be human-powered. The 12" bandsaw is of more recent manufacture and came to me with a 1/4-horsepower electric motor. I use all of these tools regularly. However, I will describe the bandsaw in some detail as it is by far the most used.
The saw is mounted on a purpose-built stand equipped with wheels. Without an electric cord, it can be easily moved around the shop or into an adjoining room. In place of the V-belt pulley driving the lower wheel is a cluster gear/freewheel mechanism from a 10-speed bicycle. A bike chain connects the freewheel sprocket to the treadle in such a way that for every 1" of treadle movement there are 2" of chain movement at the sprocket. This gives a higher speed to the saw and a better balance of power available. As the treadle is depressed, it spins a spool, winding up a cord which flexes a spring. The energy stored in the spring returns the treadle to its starting position.
I have been surprised at how fast this tool can cut wood. When sawing softwood up to 1" in thickness or up to 3/4" in hardwood, the treadle saw is as fast as the electric version – both tools must be slowed down from their maximum speed capability in the service of accuracy. Heavier cuts demand incremental progress, advancing only on the foot’s down stroke. This action mimics that of a hand saw. It is still the quickest way to rough out a heavy locust cleat.”
– Harry Bryan, excerpt from “Intermediate Technology in the Shop: Inspiration from E.F. Schumacher’s Small Is Beautiful” in Issue Eight, available here.