N3RN wrote:
> What I'd appreciate now is some advice regarding how to get the
> antennas down safely.
> If I cut the mast at the top of the tower, would it fold over
> gently or snap off? ( I know Murphys Law.)
It will snap off, taking you with it.
I was faced with a similar situation a few weeks ago. It was one of
the most unpleasant tasks I've had to perform on my tower. In my
case, I had something like 5 m of mast, with a 40 m beam at the top.
My advice: Get the tallest ginpole you can, and erect it to
protrude as high as possible above the tower itself. Guy the gin
pole in several directions if necessary for sufficient rigidity. The
guys must not stretch! Wire rope is a good choice.
You now have a means of anchoring yourself, and of lifting the
antennas off their mounts one by one. Remove as many antennas as you
can, to lower the centre of gravity.
Now support the mast itself from the gin pole pulley, and cut it
BELOW the thrust bearing. Use the gin pole to keep it upright, and
lower the mast into the bearing. Once the main kink is through the
bearing, cut the mast again and drop it straight down the tower.
If the kink is too sharp to drop through the thrust bearing, you have
a real problem. A crane or a helicopter might not be a bad
investment.
Chris R. Burger
ZS6EZ
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