Fence posts are a crap shoot. I've used 16' of 1.5" top rail as a gin
pole, but the strength and temper can vary widely. IOW, you don't know
what you are getting unless they publish a speck sheet, or the vendor
can/will demonstrate the strength and rigidity.
Hams are innovators, or at least many of them are.
Having spent my first 21 years on a farm, I had an early indoctrination
on re-purposing materials and items. I'd have made Primatave Pete proud!
Using EMT, fence posts, fence rail, water pipe, black iron, have worked
for some, but most of these materials are not thought of as good
material for masts. I've seem all up to and including one inch bent with
hand operated conduit benders. Admittedly the 1" was beyond my
abilities. Using anything that can be bent by hand causes second
thoughts about using it as mast material.
I have used iron pipe to a rotator down in the tower and extending only
a few feet above the top. It wasn't my first choice, but I already had
it. OTOH Iron pipe, be it galvanized or black, is "HEAVY" compared to
steel mast. When you look at the strength differential, the iron pipe
is really heavy for what little strength it has
EMT (also called "thin wall") is designed for indoor use and to be
easily bent with little spring as is iron pipe. Iron pipe is what is
used as rigid conduit "outside"
There are instances where these have all been used as masts successfully
and many instances...where they failed.
All of these can be used within their limitations and with the exception
of the steel fence pipe, they are consistent
I went to a small firm that installed chain link and security fences. I
asked him if they had anything in the 1.5 to 2" range that was strong
and not easily bent. He pointed out the 1.5" rail and said it's all of
those, but you might find it a bit springy.
I still have it, but that was probably between 20 and 30 years ago.
73
Roger (K8RI)
On 3/13/2016 Sunday 10:49 AM, Hans Hammarquist via TowerTalk wrote:
Try fence posts. I bought mine at Lowes. I think I payed $12 or something
around that. I have the rot(-at-)or on a plate about two feet below the top of
the tower. The post (tube) sticks out about 2 1/2 feet above the top. (The
tower is 85 feet. Too much for an installation with the rotor on the ground).
Hans - N2JFS
-----Original Message-----
From: Timothy A. Holmes <taholmes160@gmail.com>
To: Tower Talk <towertalk@contesting.com>
Sent: Sat, Mar 12, 2016 7:53 pm
Subject: [TowerTalk] Mast Material
HI Folks:
I have been blessed with 30 feet of tower given to me by a friend. its
in good shape consisting of 2 regular sections and a top section. I
also have a very solid base in place that will support it and it will be
tied to the house at 12 feet up.
My question now is the mast to go in it. I have looked at the very
heavy duty mast such as marketed by DXE and others. Fantastic stuff,
but quite expensive. I am wondering about an alternative material.
Such as thick wall electrical conduit (AKA EMP). What I would like to
do is make a LONG mast so that the rotor is at a height that is
accessible at the ground, and run it up through the tower and out the
top with about 10 - 15 feet showing out the top.
It will be carrying a 3 element tribander, 3 element 6m beam, a 9
element 2m beam and something yet to be determined on 440. (Probably not
real huge)
I need your thoughts and input, obviously I dont want it to fail and
damage anything
Thanks a bunch
TIM
W8TAH
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73
Roger (K8RI)
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