Here are some pix of my dual mast. This one has replaced to single 1.5" schedual 80 that bent at 4 ft above its support. I'm flying a set of 7ft Lakota blades on a 2025 watt motor conversion.

This is the under side of the top bearing.

This is the top side of the top bearing.

This is the black schl. 80 that will come through the top bearing. Top bearing is removed.

This is the platform at the bottom of the mast. The "A" hub keeps it secure to the platform.

This is the big flange bearing under the platform. The 1.5" mast is supported by this bearing and the top bearing. The hole mast turns and yaws with the wind. The genny is mounted solid to the 1.5" at the top. Wire will come down the center of the 1.5" #80 pipe.
2" pipe is 8 ft long and stationary. The bearings alows the 1.5" #80 mast to turn inside the 2" pipe. The 1.5" #80 pipe is 10 ft long.
The 2" pipe is supported up to 44" from the top and the top bearing.
OK thats my update. Had very strong wind today and its working very well.
JK TAS Jerry