[TowerTalk] Prop Pitch Speed Up

[Tom Osborne]

Hi All

Here's something I found in the 1949 June QST that might
be of some interest to the guys with prop pitch motors.
The article was "Speeding up prop pitch beam rotors"

Here's a way to speed up the rotation of a prop pitch without
external speed up gears, V-belts or speeding up the motor
until it burns out.  Here's how it's done--remove:

     1)  the bevel gear;
     2) its thrust bearing plate;
     3) the upper case of the speed reduction unit housing;
     4) the large ring gear with the spline on it;

This last item is the first thing you will see upon removing Item
3.

Grind the teeth off the hardened splined ring gear. (Not off the
splined portion, but off the inside of the ring!)  Next drill and
tap
four holes in the gear carrier over which the ring gear was
placed.
Line up the holes with the holes that already exist in the face
of 
ring gear, and bolt the two together.  Reassemble the whole thing
and fill it with oil.  You can now turn your beam at 4 or 5 RPM. 
To reduce this to a more-comfortable 2 RPM, it is only necessary
to reduce the voltage to the motor.  Don't worry about the slight
reduction in power caused by "short circuiting" one of the
several
planetary gear sets.  It will still have enough steam to "rotate
the
house should the beam get stuck."

This original article appeared in "Hints and Kinks" in the
magazine
and was written by W2VLL

73
Tom W7WHY

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