In a message dated 98-05-24 11:34:24 EDT, kg5u@hal-pc.org writes:
> What if you placed a gin pole above the top of the tower, dropped
> the line down through the thrust bearing (TB), and then down
> through the mast to loop through the bottom (use a wirerope
> thimble to guide and protect the rope around the mast edge) and
> tie the rope to the low end of the mast?
>
> You could even plug the top of the mast so that the rope is
> "centered" and does not abraid against the edge.
>
> It would only require guidance at the thrust bearing.....
>
> Would that work?
Sure, I've used it before. There are several problems though. Due to the
ginpole leg clamp fixture, the actual pickpoint is even further away from the
path the mast is taking. Now you've got a sideways pull on the ginpole instead
of the more desireable vertical one.
Don't forget the Rohn ginpole is only rated up to 70#, the weight of a
45G section and not a 130# mast.
Another problem is that you've got your haul rope going over the sharp
top edge of the thrust bearing where it'll abraid your rope.
So you've got an overloaded ginpole, an off-set pull and damage to your
haul rope. Other than that, it's okay.
Cheers, Steve K7LXC
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