> > The top section is the hardest because the thrust bearing
> and plate
> > add a
> lot
> of weight to the top of that section. We did get it after
> some struggle. It is hard to get the rope in the right area
> so it does not flip. Almost had to use a trail rope on the
> bottom section to steady it.
>
> This is a hard won lesson. The LXC Sub-Prime Directive
> is to "Break tasks into their smallest, bite-sized chunks and
> do not try to do two things at once"; e.g. bringing up a
> beam with the coax attached, pulling up a tower section with
> plates, thrust bearing, etc., bringing up a section with the
> guys attached, etc. Everything is much easier when you do it
> one thing at a time.
I agree with this "Directive" in general, but sometimes exceptions can make
sense. When dismantling three highly corroded towers in Aruba two weeks
ago, I opted to remove the top section (of Rohn 45 and, in two cases, of
Rohn 25) with the rotor plate, rotor, top plate, thrust bearing and mast in
tact. This was because they were heavily rusted and difficult to separate,
especially at height in the high winds at the time. However, we had to
account for safely dealing with the much heavier top sections as they were
carefully lowered to the ground. No compromises should be made in the
gin-pole/pull-rope/lowering system.
73,
Ed - W0YK
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