KiwipropsTM
The Kiwiprop™ is a unique cost effective feathering propeller that eliminates gears, aligns the blades with the streamlines not the shaft, minimises corrosion potential from the lightweight composite blades and offers users easy variable pitch adjustment
The Kiwiprop™ is now available as the result of a long and careful development program that was designed to bring new levels of performance and value to the sailor who wishes to retain the known benefits of a fixed three bladed propeller, for motoring and maneuverability, but at the same time minimise drag under all sailing conditions.
Traditionally feathering props have blades geared together, to ensure that they line up with the shaft when feathered. However the shaft rarely lines up with the water flow, thus increasing projected area and thus drag. With a typical inboard engine the shaft will be angled down at 10 to 15 degrees and with the hull sloping up at say 5 to 10 degrees, the shaft may be 15 to 25 degrees off the streamline of the water flow. This can cause auto-rotation and wear with the need for shaft locks. In addition there can be 5 to 10 degrees of leeway on the wind and surging sideways in big waves.
In the Kiwiprop™ designs - the individual blades are always free to "weather vane" in the actual water flow, to a minimum drag position so don't cause autorotation.
This modern light weight three bladed feathering propeller has proved much smoother and quieter in operation than equivalent two bladed units and offers the additional benefits of variable pitch, is fully lubricated with minimal corrosion potential and offers full reverse thrust.
You have now reached the new KiwipropsTM website. Kiwiprop K3 units has now been in production since 1995 with many thousand installed world wide on a huge range of vessels and drive trains. The SDC or Sail Drive Composite unit having completed Beta testing is now available for purchase. Some of the feedback associated with this testing program are on our website.
With the SDC unit in production and a further composite folding propeller in the design pipeline we decided that it was time to amalgamate the sales and promotion of the full range of Kiwiprop™ units. All have in common the extensive use of glass reinforced composites to address weight, corrosion and economic design issues. You may find these of interest:
The new K4 unit will be available October 2011 with four composite blades on a Stainless Steel blade carrier and boss. This unit is designed for higher horsepower installations, and installations where for larger vessels, additional blade area is required. We have a trial unit in the water and an initial production status run of units in process. These will be also put in service for real world testing for size confirmation and further testing as we start without sizing benchmarks for the popular installations that we can recommend with confidence. Variable pitch always allows for fine tuning to optimise any particular installation.
Many of the design features of the K4 unit are identical to the K3 that now has some 16,000 plus propeller years of service. We are confident that identical features such as blade attachment and pitch adjustment will perform in the same reliable manner as in use on the well proven K3 unit.
The K2 ultra light weight folding unit with all composite blades and boss is in the final testing stage. We have been refining this design and aiming for a very low weight - we are estimating a finished weight of 2.0 kg! - with a lower initial cost unit for small horsepower engines where a 3 bladed feathering unit will have a price disproportionate to the vessel. The initial 3D prints of these units have taken place and we are now continuing to refine the design for ease of assembly. Further updates will follow as testing is completed.
The SDC unit which targets the unique requirements of Saildrives is now available - initially in 2 bladed configuration.
Full details are available on this web site
We hope you find the website informative. If there is further information you require please drop us an email.
