[TowerTalk] Mounting a Cushcraft R8

[Michael Tope]

I am getting ready to install some kind of multiband vertical
at the QTH of a bed ridden friend, so he can hopefully get
on HF during his extended convalescence. Last week I
stopped by his QTH just to look things over. His house is
a 2-story with a large ~(6" x 10") ridge-beam running along
the peak of the roof from one end of the house to the other.
The ridge beam sticks out about two feet from either gable,
so we were thinking that this might be a convenient mounting
point attaching the base of a multiband vertical.

My question is, will I be asking too much from this beam
if I try mounting a Cushcraft R8 off the end of it without
any guy wires? The Cushcraft R8 is 28' tall, and based
on my quick and dirty back-of-envelope calculations,
it would generate around 800 ft-lbs of overturning
moment in an 80 MPH wind (the rated wind speed of the
R8).  I think I can come up with a suitable bracket that
will distribute the load from the base of the vertical evenly
across the exposed surface area of the ridge beam, such
that the base of the vertical and the beam will form a fairly
rigid assembly. I am mostly worried about twisting of the
beam when the wind is blowing perpendicular to its
axis. Any thoughts from the group?

Thanks,

Mike, W4EF............