Propeller calculation When you switch to another propeller, it is strongly recommended to have the propeller recalculated. Each propeller brand has its own characteristics. When you simply take the size (diameter and pitch) of your current propeller and buy another type propeller, you run the risk of losing efficiency of your engine. Each propeller is calculated for the purpose. To be able to calculate the propeller we want to know from you: name Email What kind of propeller are you looking for? Folding propellerFeathering propeller Propeller rotation: LeftRight Type of boat Waterline length(Meters) Ship weight(Kgs) Engine brand Type motor GearboxSaildrive Power(pk) At revolutions per minute Reduction of the gearbox or saildrive :1 of saildrive Required details for non standard shaft tapers Please fill in this section for dimensions from the shaft OR the following section for dimensions from your propeller: A:Thread Diameter B: Taper Small end Diameter C: Keyway Width D: Shaft Diameter E: Taper Length F: Thread Length Or existing propeller hub details A: Taper Length B: Keyway Width C: Taper Small end Diameter D: Taper Large End Diameter Should you suspect that clearance may be a concern, please supply the following measurments A: Approx Angle in degrees B: Tip of shaft to nearest obstruction C: Centre of shaft to Hull Above measurements are in: MMInches Remarks: