Mast ouch!!

[K7LXC@aol.com]

Greetings, TowerTalkophiles --

     I just got off the phone with a guy looking for a chromoly mast.  Since
TOWER TECH doesn't handle them (yet), I gave him the number for Tom, K5RC, at
Productivity Resources.

    It seems that this amateur was installing the top tower section of his
tower replete with mast and antennas installed on the top of his tower
section with the help of a crane.  He had a small stack (2 or 3 antennas, I'm
not sure) of Telrex monobanders on the mast and during the lift, for whatever
reason the load shifted and the mast bent.  He had everything installed on an
aluminum 6061-T6 mast.  Boys and girls, this type of mast material only has
35,000 psi typical tensile strength and should be used carefully for ANY mast
application.  A TH6 six feet up the mast in a 100 MPH wind exerts almost
80,000 psi pressure on a mast!  

    This guy was in a 105 MPH hurricane zone in Florida!!  That's the MINIMUM
wind speed to consider for this installation.  He might even want to go to
110 or higher to increase his reliability.  Jeez, what an uninformed decision
to make.  I know that everyone out there in TowerTalkLand knows better.  At
least you'd ask before embarking on this ill advised course.

    When I looked up his wind zone in my TIA-222 and told him, his remark was
that he was shielded by trees and very rarely got anything over 50 MPH.
 Hello?!  Is anyone home there?  At least he realized he should get a robust
mast.

73,  Steve  K7LXC

    TOWER TECH -- professional tower supplies and services for amateurs

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