Introduction

The purpose of this test is to examine blade to blade consistency of our four blade propeller compared to quality aluminum propellers.
 

PITCH COMPARISON

RAKE COMPARISON

TRACKING COMPARISON

 
Above are several charts made possible by Revolution Technologies, a Seattle company that has developed a very precise propeller measuring apparatus and analysis software called The Blade Runner. We asked them (as an independent service) to analyze one of our 4 blade props and several other aluminum 3 bladed propellers that were chosen randomly then sent to Revolution Technologies for their analysis.

The Blade Runner equipment can make measurements to the accuracy of one thousandth of one inch (.001") to compare blade pitch, profile, rake and height. It must be stressed these graphs do not compare one prop to another prop; they show how consistent blade shapes are on a blade to blade basis on the same propeller. It is extremely important for all the blades on a propeller to be identical to each other to achieve maximum performance and minimum vibration. These graphs depict how closely the propellers checked actually approach that goal.

Propeller Consistency

We at CMP address propeller to propeller consistency by pointing out our injection molding method of manufacturing gives us a clear advantage over other manufacturing methods. Aluminum die cast propellers (Mercury and OMC) and sand cast propellers (Michigan) cannot maintain the same consistency as injection molded parts.

While die cast raw castings can be consistent out of the mold, variables come into play during the secondary operations which can be extensive. Machine and hand operations such as reaming, grinding, balancing, hubbing and painting may contribute to differentiation between one propeller and the next. Sand cast propellers have the above operations plus the additional handicap of casting and pattern irregularities.

In contrast, our injection molded propellers require limited flash trimming and the welding of a flair ring. Without question, injection molding yields the most consistent parts of the three manufacturing methods.

Summary

All of the props tested are quality propellers. It was our intent to determine how COMPROP blade consistency compared to top-of-the-line aluminum propellers. These independent test findings illustrate COMPROP blades have the highest degree of uniformity and consistency. This is a real advantage. We feel our blade accuracy is one of the reasons on-the-water performance testing has shown the new four blade COMPROP to be as fast or faster than aluminum propellers.

I hope you find these graphs interesting and informative. If you have any further questions about this analysis, or require additional information, we would be happy to provide it to you.