Why Do SEAHAWK use stainless steel and not bronze like other propellers?
SEAHAWK have been manufacturing propellers since 1976 and begun using stainless steel in 1998. Whilst bronze is an excellent propeller material, it is difficult to cast the accurate and complex shapes, required for a product like a feathering propeller, this results in almost 100% machining of all surfaces. Stainless steel can be cast more accurately and in complex shapes using a casting method known as lost wax or investment casting. This allows greater scope for innovative design: also machining costs are reduced, as only very accurate surfaces need to be machined. The outside surface of the body and the propeller blades are only polished. In most installations the propeller shaft is also stainless steel and being a common material to the propeller there is less likelihood of electrolysis occurring. Why don’t other feathering propeller manufacturers use stainless steel? The tooling cost to set up for investment casting is much more expensive than for casting in bronze. Other manufact
