• Precautions are necessary to prevent the propeller jumping at release. A development of the keyless method involves a cast iron sleeve which is bonded into the propeller boss with a special form of Araldite which is injected under pressure. The sleeve is machined and embedded to the shaft taper but can be used to adapt a general purpose spare propeller to a particular shaft taper. The sleeve is easier to handle when machining and bedding than a complete propeller. Another benefit is that cast iron has a coefficient of friction nearer to that of the shaft than to the propeller bronze

Sleeved propeller

Cross sectional view