Here is my 2 cents on a long and interesting thread...
My original installation was 90' of 25G on a windy hilltop.
20' of 2" schedule 80 mast with 10' in the tower.
Antennas 204BA, 4el Cushcraft 15 and a 6el homemade 10 turned by a
Tail-twister. OK kinda crowding that 10 feet but it did play well!
Lesson learned #1 - dont use schedule 80 or a TX2 for this load in a rough
environment.
The rotator and mast lasted 6 weeks.
Replaced the mast with 2" schedule 40 stacked with the next size down inside
(almost 1/2" wall) and a Create rotator.
Lesson learned #2 - never use water pipe for mast... It bent after about 1
year.
Replaced mast with 15" of "real" Texas Tower stuff... Replaced antennas with
a 3EL 20M Telrex and a 3 el 40M Mosley (big beast!!)
New problem - slippage... So I drilled out the mast clamp holes in the
Create so I could go to the next larger (8MM) Grade 8 bolts.
Bad Idea!! The clamp held but I stripped gears in the Create within 6 months.
By now, the original Orion came out, so I upgraded the rotator. The Orion
definitely had a seriously robust mast clamp (6 3/8" bolts)... Yippee - NO
SLIPPAGE
Everything was fine for couple years... Then the drive shaft parted from the
final drive gear (the weld joining them failed). Note - anyone who has ever
looked inside an Orion knows these parts look indestructible.
After a real pain jacking up the mast / antennas and dropping the rotator and
replacing the gear everything was fine for another few years when once again,
the same thing happened.
All things considered, reorienting your antennas is a lot less of a pain and
a lot less expensive than trying to prevent slippage. You may accomplish a no
give clamp but you run the risk of trashing the rotator. After going through
this 4 times within 8 years, I'd rather climb the tower and re-aim the
antennas.
73 de Bill
K2EK
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