Rick (W-A-one-R-K-T) wrote:
What do you all think of using heavy duty nylon rope instead of wire for
guys?
For a temporary (few week) installation?

Nylon degrades in UV
Nylon is quite stretchy, so you'd better be willing to tolerate a lot of
deflection under load.
Nylon is challenging to attach without severely weakening it (i.e. you
can't just tie any old knot)

OTOH, if you're talking about using something like 11mm static climbing
line and a short tower, you'll probably survive.



I have a Rohn 25G up 50 feet with a 2M/220/440 vertical on a 10-foot mast
on top of the tower. It is guyed at 30 feet with standard steel guy wire.
I was just up the top of it two days ago installing the vertical, and it
seems rock solid.

Now my next project is to put up a 3-element tribander, and while my guess
is it'll probably be OK without any additional guying, the paranoid in me
says "hey, bozo... put up another set of guys!".

Run the calculations and see..
Make your own risk assessment..

Your guys attach about halfway up, so you've got a situation where
there's a fair bending moment on the tower, as well as the usual
compression loads on a guyed tower. Bending loads are bad, because they
tend to aggravate the existing tendency to buckle.



I'm wondering if heavy duty nylon rope will be sufficient. It'll sure be
easier to work with, and there won't be the issue of having to break up
the guys every so often to keep them from resonating.

There is a ham on the other side of town that has FOUR (4) Rohn 25G's up
120 feet each, arranged in a square, and fed with a phasing network as
phased verticals for 80 meters. Each of the four towers is guyed in two
or three places with polypropylene rope. Been up a long time and seems
OK. But, there isn't a tribander and rotator on top.


Sure.. but what you describe is an anecdote, not an analysis. Compare
the kinds of rope (polypropylene vs polyamide (nylon)) and their
respective strengths, aging properties, and elasticity. Compare the wind
loads and their distribution, etc.

The short answer is "probably".. how close to "sure" do you need to be?
A temporary tower in the middle of a cow pasture for a weekend is a lot
different than a permanent installation in a suburban area.