K7LXC said:
> Ah, amateurs vs. knots. Unfortunately most hams don't know any knots.
Sad but true. Most of the time, a bowline and a couple of end-to-end
rope-splicing knots will go a long way for most ham antenna work. Good
knots are easy to tie, stay tied when you want them to, and easy to
untie when you're done with them.
> The knot I would use is a clove hitch. It's pretty simple and
> self-tightening. It's in any knot book or website.
Yeah, but one of the Web pages that the "icicle hitch" Wikipedia entry
led me to showed several vastly superior knots for this purpose, such
as the Prusik knot:
http://www.animatedknots.com/prusik/ and here:
http://www.chockstone.org/TechTips/prusik.htm
Incidentally, if you look at the entry for the clove hitch on the
animatedknots page, it says:
"In many situations if you feel an urge to use a clove hitch - resist!
Choose something else"
I would consider that a "Prime Directive".
It really is not a good choice for lifting a mast. The pull when
lifting a mast is in the wrong direction to make a clove hitch
self-tighten. I've used it successfully for lifting a boom that is
parallel to the ground, though. However, these new knots that this
thread (no pun intended) has turned up look lots better, and I expect
to use them from now on.
> But the even simpler solution is to use nylon slings. I always carry 6-8
> of them when I'm doing tower work and sometimes I use all of them. They are
> 1" nylon webbing that's sewn together giving you an endless loop 12-18" long.
Turns out I saw (on a page that I unfortunately didn't bookmark) a
Prusik knot made with a nylon sling - basically a choker with the free
end looped through 3 or 4 times. The pull on the mast DOES tighten
such a knot. I have seen another well-known tower climber/installer
use it without calling it by name. The free loop can take a carabiner
and you're good to go.
> And I recommend putting a muffler clamp above the rope to act as a
> stopper in case the rope slips.
This is a good idea.
> Installing big, long heavy masts does produce a good-sized pucker
> factor.
Very true!
> Be careful in any case.
The Ultimate Prime Directive!
73 and Happy New Year to all,
Doug K1DG
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