Glenn, K6NA wrote:
> >In a magazine several years ago, I recall seeing someone order 2
> >extra sets of equalizer plates (the triangular things with holes for
> >either 3 or 5 sets of guys) from Rohn. They then welded a single
> >plate (the edge with the multiple holes) to the post, and attached a
> >regular set of plates to that plate with the included bolt. Still
> >worked as an equalizer plate, too.
>
> This looks like an unsafe idea. A single Rohn equalizer plate looks pretty
> wimpy to me, although as a pair they are obviously okay. But a single one,
> welded to the pipe, seems unsafe as it is 1/8-inch thick, at most.
Glenn, I respectfully disagree on the heft of the plates. Although I
couldn't find specs for the thickness in the Rohn manual, I did go
out and look at mine, and they are at least 3/16". I don't mean to
split hairs, but I don't think they are at all flimsy.
Anyway, a more important consideration that hasn't been addressed is
the welding of galvanized material. I am not a welder or a
metallurgist, but I have been told that there is more to welding
galvanized steel than just striking an arc. There is then the issue
of rustproofing.
A local QRPer, when putting up elevated guy attachments, used 10"
wide flange I-beam, and had a local blacksmith strike off part of one
plate and the web at an angle, then drilled holes in the web to
accommodate jaw type turnbuckles.
For well casing, or the like, I think the best idea is the eye bolts,
with the emphasis on FORGED EYEs.
Incidentally, Dick, K5IU, addressed the engineering of elevated guys
using I-beams at the W9DXCC a few years ago. And he stated that he
found engineering data for the stresses applied to them in a book on
billboard installation.
73, Rod N4SI
The DXer formerly known as N9AKE
(c) 5 November, 1996
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