This is not rocket science, gentlemen! All that is needed to hold tower
sections together is an ample amount of stress applied to the fastener to
tension the outer surface against the inner formed mating surface
sufficiently so it stays in the proper prospective. Gravity and guys hold it
all together. You just need to insure that the outer leg doesn't split from
the weight load plus the guy load. Rohn supplies fine threaded SAE bolts and
nuts. I've been using and re-using S.S. hardware and never-seize compound on
my towers for over 35 years and nine relocations without any problems to
this day. I've seen the original Rohn hardware break upon attempted
disassembly after less than four years. The S.S. hardware always has come
apart clean and easily and with a new coating of never-seize, is put back
into the same service, again and again.
Unless you are exceeding the total recommended tower height and antenna load
weight and the hardware is torqued to the recommended stress level, just
about any steel hardware of proper diameter for the holes will work. Its not
a case for shear unless the bolts are not tightened sufficiently. They must
have ample tensile strength to compress the outer leg against the inner leg,
thats the only requirement. Rust and corrosion are other factors for safety
and longevity. S.S. hardware wont rust or corrode. In most amateur radio
tower applications of moderation, wooden alignment dowels and 1 1/4" ID
muffler clamps positioned and torqued properly would suffice in Rohn 25
assembly! Any proper size bolts, properly tightened, will do an ample
job,...initially. Your mileage may vary.
It would be good to move on to the TenTec reflector designated subject
matter and take further tower discussions to the towertalk reflector where
they belong.
FYI;
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
Rog-K9RB
----- Original Message -----
From: "Dave Kamp" <kw0d@netexpress.net>
To: <geraldj@isunet.net>; <tentec@contesting.com>
Sent: Monday, October 20, 2003 4:41 PM
Subject: Re: [TenTec] rohn 25
> Actually, I took two of these down just a few weeks ago- it sounds like
it's at
> least partially correct to me... Rohn 25 requires two bolts for each leg,
and
> they differ in diameter and tool-flat size. If the field-day tower is 3
> sections and a top section, it should require 12 bolts of about 3/8"
diameter,
> and 12 bolts of about 7/16" diameter. Note that Rohn bolts are
fine-thread, and
> when inserted, the bolt's unthreaded 'neck' will extend right up to the
outside
> edge of the leg, so that when you torque it, the nut will slightly
compress the
> leg, and bottom against the bolt's neck. The neck will also completely
fill the
> tower leg hole, not just 'drop in', as this allows the inner and outer leg
to
> 'shear' the bolt and maul the tower-leg holes. It'll also generate enough
yukky
> noise in your Ten-Tec that you'll want to use the 'real' bolt...
>
> DK :-)
>
> Quoting "Dr. Gerald N. Johnson, electrical engineer" <geraldj@isunet.net>:
>
> > Some one has drilled out some of the holes for larger bolts they had on
> > hand...
> >
> > 73, Jerry, K0CQ
> > Stuart Rohre wrote:
> > >
> > > I believe when you get to the top section, there are differing bolt
> > sizes.
> > >
> > > Our club has about 40 feet of Rohn 25 and it takes two differing sizes
of
> > > nuts and bolts to assemble for Field Days.
> > > -Stuart
> > > K5KVH
> > >
> > --
> > Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
> > Reproduction by permission only.
> > _______________________________________________
> > TenTec mailing list
> > TenTec@contesting.com
> > http://lists.contesting.com/mailman/listinfo/tentec
> >
>
>
> _______________________________________________
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>
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