The title says it all... We had an apparent microburst or severe
downdraft or whatever they want to call it. Anyhow, it took out a perfectly
healthy 60 foot Oak which took out a set of guys which in turn took down my
60 foot tower and assorted antennas.
My dilemma is, since my bottom section was a piece of 25g that had been
cut off at concrete level by the previous owner and, my tower bent at about
the 5 foot level which - of course - is just below the first joint, what are
my best options. I suspect that sawing the remnants off at concrete level,
plugging the holes, and installing a mounting plate is going to be a lot
less painful than trying to jackhammer a yard of lazy aged concrete into
manageable sized chunks. I notice that Rohn offers a Pier Pin mount and also
a mounting plate with 4 mounting holes and stubs for the first section to
mount to. There is about $50 difference in the price so that is not a real
issue. Just wondering if anyone has any pros and cons to offer on the
choices.
As for loading, I intend to return to the previous 60 foot level and the
tower was (will be) loaded as follows: Force12 C4 or maybe a C4SXL (C4 was
the previous installation); Cushcraft A505 6 meter 5 el beam or equiv.; M
Squared 2M7 7 el 2meter beam; FO25 25el 432 beam; and a Hustler G6270R
2m/440 vertical on top. The mast was about 19 feet of 1026 alloy .180 wall
tubing with about 5 feet of it in the tower. A wooden bearing was on the top
plate and a thrust bearing was on the rotor shelf, with the rotor 2 rungs
below that. Guys were at the 35 foot and top shelf levels.
Back on the subject of the mounting plates, what is the proper procedure
for attaching something like this to a concrete base and where do you look
for whatever materials are required. I know this has been discussed before
but I naively thought I would never need to know that sort of thing since my
tower was going to stand forever. Oh well, I imagine that's what that 60
foot Oak thought too.
Thanks,
Mike / W8DN
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