SSYTC056 A ‘new’ tablesaw engine
Episode description
At the local school fete, and the local (Port Philip) historic machinery society come each year with their eclectic collection of vehicles and machines.
A few looked like they would be ideal for powering a belt-driven machine, or a small workshop line shaft.
One I particularly looked at was indeed a motor that originally drove a tablesaw.
It is a 2.5HP petrol engine by the Sandwich Manufacturing Co, from 1926. It has a magneto ignition, and runs around 425RPM
It may be a 4 stroke, but when you watch the video, the movement of the lever under the magneto unit, and the valve operation is just how slow the firing rate is when the engine is idling.
A simple, clever regulating system means it just ticks over, firing the piston only when the motor slows below a certain speed. An impressively fuel efficient system. As load increases, the firing rate also automatically increases.
The ‘pot’ of boiling water is the cooling system. Instead of a radiator, the water is allowed to boil away, with the energy required to transition the water to steam being an effective method to pull heat out of the engine. Of course you have to monitor the water and oil level! The oil drip-feeds the engine, with just the required amount gravity fed in each stroke, which then works down past each surface needing to be lubricated.
An impressive unit from a bygone age.
SSYTC056 A ‘new’ tablesaw engine