Sawing a Board

As the sash holding the blade moves up and down, connecting levers at the top move a metal bar, or ratchet. This ratchet engages teeth on a ratchet wheel and pushes the wheel forward with each stroke. Wooden teeth on the shaft of the turning ratchet wheel engage cogs on the underside of the carriage. The carriage and the log are then pushed along wooden rails, advancing into the saw blade. The carriage is returned for another cut by manually turning the ratchet wheel backward or by pulling a press pulley against it. The press pulley is in turn powered by the tub wheel underneath.

Maryland · United States