[TowerTalk] Rohn 45 foldover questions

Stan Griffiths w7ni@teleport.com
Thu, 13 Nov 1997 11:11:27 -0800 (PST)

>questions; how easy/difficult is it to un-tension and detach the top set of
guys prior 
>to folding over - can it be a single person job?

Yes, a single person can do it.  Loosen the all the turn buckles on the top
set first so all guys are slack.  Then disconnect each guy entirely, maybe
by simply unscrewing the turnbuckle the rest of the way.  You may need some
help to get the turnbuckles screwed back together, or you could easily do it
alone with the aid of a come-along.

  What type and how often does 
>maintanance need to be done on the winch, cable, foldover section etc.

Winch and cable cautions are the same as for any crankup.  Careful periodic
inspections are necessary.  Periodic cable replacement is recommended but I
don't know how often.

  Are there any 
>reports of disasters/failures during the foldover process?

I witnessed one at K6EBB in 1969.  It was a 25G crankup and it was simply
loaded too heavily and with one too many sections above the hinge.  When it
was just horizontal, the tower leg joint just above the hinge gave way as
the leg bolts pulled through the bottom of the tower leg causing the tower
to "fold" in the wrong place!

  How does the Rohn foldover 
>concept compare with crank-ups?

Rohn tilt-overs tend to be a lot safer than crankups, in my opinion.  There
is no "guillotine effect" with a tilt-over as there is with a crankup.  You
can actually safely climb a tilt-over when it is securely guyed and the
hinged section is clamped into place with the Rohn hardware provided for
that purpose.

One of the BIG mistakes made by crankup owners is the assumption they make
that the tower will be cranked down in a wind storm.  Unless you crank it
down after every use, it will probably be up when the wind hits.  It is too
late to crank it down then since most crankups bind in a wind and won't come
down . . . except damned fast and when you least expect it . . . unless you
own one with the "positive pull-down" feature (and then you have to be there
at the right time).

If you motorize your crankup, it may well be down in a wind, but since you
will do a lot more "up" and "down" with it, there will be a lot more wear
and tear on the winch, motor, pullys, and cable.  This means more
maintenance and more things to fail such as limit switches.

Most tilt-over owners do not expect to tilt it over in a wind and they
expect it to be able to take the biggest expected wind while fully "up".
Tilt-overs tend to be more reasonably loaded by their owners and therefore,

>Any info and experiences on the topic will be appreciated.

Hope this helps you decide what to do.

Stan  w7ni@teleport

PS  YES, I sell tilt-overs for profit, and NO I don't sell crankups (except
for the one used one I have sitting here, W-51, I obtained in an estate
sale).  If you think my opinions are biased against crankups because I don't
sell them for profit, you are wrong.  I don't sell them because, I have a
conscience, I and believe they are inherently dangerous to the average ham.

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