Thursday, September 29, 2016

Gizmo Geezer Review - Part 1

This is the first part of my review of the Gizmo Geezer rubber power propeller system which relates to my testing on a stand and the installation in an existing P30 free flight model I have.

Testing Gizmo Geezer on a Stand

Desirable features I saw in Gizmo Geezer Advertising

  • No additional method needed to hold nose of the model on such as rubber bands or magnets.

  • Method to do easy thrust adjustments without having to use shims.

  • Smoother unwinding of rubber motor and no need to braid the motor. 

  • The propeller would free wheel easily without the need to build additional mechanism on the propeller shaft.

  • The propeller has a higher PD ratio than similar propellers.

Getting Started

The rubber motor loops are attached to the Sleeved Clevis by inserting Sleeved Clevis Pins.  Attaching the rubber inside of the Sleeved Clevis can be a little tricky but if you gather the end of the rubber together in a bunch and work the hex wrench through the small loop with the Sleeved Clevis pin inside it goes into place fairly easy. Here I have 3 loops of 1/8” rubber.

Rubber has been inserted as seen from the rear.

As seen from the front.

The Winder Attachment is connected to the front of the Sleeved Clevis by inserting through the slot and then twisting.

Your winder is attached to the loop in the back of the Winder Attachment

After the motor is wound it is inserted into the rear of the Prop Shaft Drive and twist to connect.

After the motor is wound you can park the motor such that you do not have to hold the propeller to keep it from unwinding. When you are ready to launch you can engage the propeller again.   

With the Gizmo Geezer there is no need to braid the rubber strands in fact doing so will not let the free wheel mechanism operate properly.

Front view of Prop Drive Dog engaging the propeller.

Just before going into park mode which stops the rubber from unwinding further and propeller goes into freewheel mode. Keeping a level of tension should combat the problem of random bunching of a long motor that can negatively affect the glide. According to Gizmo Geezer website the tension is held to between 55 to 60 grams.

Propeller disengaged

There are three screws that can be turned for thrust adjustments.

Installation into Existing P30 Model

This is my NJAPF P30, note the ugly rubber band across the front of the nose to hold it in when all the tension from the rubber motor has gone out. Free wheeling is accomplished by 90 degree bend in the front of the shaft and the molded ramp with notch in the propeller. 

Gizmo Geezer PW95 propeller seen above which comes adjusted to a high performance 1.25 to 1 P/D (pitch to diameter ratio). Peck 9.5” propeller seen below.

To be continued..

Bill Kuhl



  1. It seems to go backwards just before the freewheel disengages. You can see the clevis stop and reverse. The prop slows down when this happens but its not clear if the prop also reverses.

  2. I noticed that too, that back of the shaft screws forward after that and puts the propeller into free wheel.