[TowerTalk] More on Orion mast clamps

[K2EK@aol.com]

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