On Mon, 15 Jan 2001 15:20:55 -0600 "Marty Purselley" <brewer@flash.net>
writes:
> I have the following that I want to put on my "new-to-me" 64 foot
> Rohn 45g
> tiltover: 2 element Cushcraft 40 meter beam, TH3-Mk 4 tri band
> beam, 5
> element 6 meter beam, and 13 element 2 meter beam. All of this on a
> 15 foot
> mast and turned with a TX2 rotor. Does this sound unreasonable?
Since your loads are not going to all be at the tower apex,
you should use the "Safe Moment about the Hinge" specification
that Rohn used in their old catalogs for the foldover towers.
For the 64' tower the safe moment about the hinge equals:
135 pounds (safe load at apex) x 35' (distance, hinge to apex)
or 4725 ft-lbs.
So, you take the weight of each antenna, mast, rotator, cables, etc.,
and multiply each weight by its distance to the hinge. For the mast,
use the distance from the mast center of gravity to the hinge. When
you add up all the moments, the sum cannot exceed 4725 ft-lbs.
> Finally, is it necessary to use galvanized J bolts? Anyone
> have a
> source for them-I'm figuring 1 inch diameter by 18 inches.
What are you thinking about here? There are normally no J-bolts
used with these towers.
Dave Hachadorian, K6LL
Yuma, AZ
K6LL@juno.com
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