Gary, it will be an extremely tight fit and I would advise against it. I have
had a Universal tower since 1977, first with a 60 footer, then 70 footer, and
since 1998, an 80 footer. In all instances, I used a long shaft to reach down
to the 18 inch section where the rotor is placed. The 14" top section is held
in place with only one bolt per leg and if you put the rotor there, you might
have too much twisting action (depending on the size of the beam) and the top
section will break. The longer mast absorbs some of the twisting action.
Currently, I am turning my TH-11 (12+ sq feet of windload) with a 1977
Tailtwister which has never been opened up. It is a very capable rotor. I have
a thrust bearing in the middle of the top 14" section but the rotor is halfway
down the second 18 inch tower section.
73, Dennis W0JX/8
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