It seems that nothing is a simple as it first appears; masts included.
The structural steel commonly used for industrial applications is usually
made of an alloy with a 40,000 psi yield strength. While this may be enough for
modest antenna loads, it is inadequate for large antennas and/or stacked
antennas. One of the computer programs will allow quick analysis of mast
stresses. This material is not galvanized and the buyer has to arrange for that
if
needed. High carbon steel material typically has a yield strength of 80,000 to
85,000 psi; more than twice the strength of the commonly available mild steel
using in construction/industrial applications.
6061-T6 aluminum is attractive from a cost and weight standpoint. Typical
yield strength of this material is 38,000 to 42,000 psi. The same big/stacked
antenna concerns apply to aluminum.
Chrome-moly is a wonderful material but it too has some issues: it is
usually shipped without heat treatment to allow easy fabrication. Heat treating
is
often done after the fabrication is complete. You can buy heat treated
material but you have to ask for it and pay for the heat treatment charges.
Typically the steel company does not do the heat treating; another company does
that. Also, there is the issue of galvanizing; the steel company is not into
doing that either.
After checking into all the issues you can begin to understand why a good,
strong, galvanized mast is so expensive; there is a bunch of work and shipping
to prepare the product properly!
73,
Gerald Williamson/Texas Towers
(we sell galvanized carbon steel and aluminum masts, tel 800 272 3467,
_www.texastowers.com_ (http://www.texastowers.com) )
In a message dated 9/10/2005 3:38:18 P.M. Central Standard Time,
kd4e@verizon.net writes:
Do you live near anyone who builds racing cars?
They use chrome-moly which is stronger than the
galvanize mast but also costly to ship. They might
sell you from their excess or let you buy into an
order they are planning to place.
The other place you might look is a metal recycling
shop. We have one near here that often has lengths
of 6061 (I think that is the number) thick wall aluminum
pipe.
doc
> My question is: What other options can I explore for masts of similar
> length & strength (I am 3 miles from the Atlantic Coast)? Are there
> other suppliers closer to Rhode Island?
>
> Thanks for any advice. 73, Brian, K1NW
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
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TowerTalk mailing list
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
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http://lists.contesting.com/mailman/listinfo/towertalk
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