Variable Pitch Propeller Design - Prototype

new.gif (1957 bytes)  22 Jan 06 - Videos added.

I have been designing a variable pitch propeller unit for experimentation and this prototype unit uses standard folding blades. The following drawing shows the principle and components of the design.

Vari-Prop Sketch

I have machined the main hub, propeller drive arms, crank arms and centre control hub. I have also fitted an old spinner front to streamline the prototype. I decided to do without the ball and thrust races for the prototype to ease manufacture (they can be fitted later if required. Additionally, if the design works well without them, there is no point making the effort to fit them. I have included a few video snaps of the progress so far. They show the propeller hub as manufactured without blades and with the blades at a mid position, fully fine and fully coarse (or feathered). The angles for these pictures was set manually as I hadn't made the shafts or ball link arms at the time.

Vari Prop oblique view Movement range
Vari Prop top view

Note: The design presented here is for experimental use only and no guarantee can be given as to the design strength. Anyone using this information for any purpose does so at their own risk.

5 Apr 04  - The following images give a better view of the assembled mechanism with the nose cone removed.

  Nose Cone removed     Close-up in fine position     View at 45, fully fine & coarse     View at 85, fully fine & coarse  

22 Jan 06  - The following videos show how the Variable Pitch Propeller works.

99kb short ASF video 1.9MB long MPG video

Model Plans & Designs