[TowerTalk] I finally figured a way to stop mast slippage

FireBrick w9ol at billnjudy.com
Tue May 4 08:35:14 EDT 2004


My old Wilson rotatable has two small bolts that serve as set screws to clamp the mast in
the tube.
Tighten the two bolts is SUPPOSED to stop mast slippage.
But I was always reluctant to really crank down on them for fear of breaking them off or
stripping them out.

I really didn't want to drill out the chrome moly mast either.
The recent 40 mph+ winds in Chicagoland had me 'correcting' for windage frequently.

So I finally came up with a design that was cheap, easy to install, and seems to have
solved the problem of misalignment.

I got two small 'clip angles' from work.
These are 4" long 4X4 wide angle irons, about 1/4" thick.

I drilled two sets of holes for 2 1/2" U bolts in one and two sets of 2" U bolts in the
other.


The 2 1/2" clamp piece was put on the mast insertion tube.
The 2" clamp piece goes around the mast.

There will be a slight difference in position due to the 'insertion tube on the tower'
being a larger size than the mast, but the two clips angles should line up in the
horizontal plane.
I then clamped them together and drilled two 3/8" holes through the horizontal plates.
Make sure the antenna is properly oriented and bolt the two plates together and tighten
all the U bolts.

Fortunately for me, my Wilson tower is right next to the large chimney on my roof so I
could stand on the chimney and easily do the final drilling and tightening.

Hope this gives someone an idea on solving a similar problem.
In my case, where the rotor is mounted at the bottom of the Wilson tower, this does not
add appreciable strain on the rotor.
In the case of a top mounted rotor, you may want to consider the slippage vs. rotor damage
before adding my clamp system.

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Only a genealogist regards a step backwards as progress.
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Bill H. in Chicagoland




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