John,
Here is an improved and simplified version of the pitch change motor as shown
on the ACRE NL web site. I checked the pitch change and it looks
like we will have around 33 degrees which should be plenty.

We will need to mill a slot in the main cross tube to allow the 
pitch change yoke to protrude  but it will be much smaller than I 
had at first thought. With a little more slimming down of the yoke 
it could be even smaller. A small hole is desirable as it causes
less stress concentrations in the cross tube.

The pitch change motor support tube could be welded aluminum bolted
to the main cross tube as there is very little load on it.
Or it could be a steel tube welded to the main cross tube.
Your choice. the motor mounting slug shown is aluminum.
The motor is bolted to this with four machine screws by means
of a square flange on the output end of the motor. I will upload
a picture of the motor shortly.

DXF under separate cover.

Paul Lamar
 
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