Well, I assume we all do it differently.
When I have generally put up my 70 (Rohn 25), 90 (Rohn 45 for all the rest),
100, and 120 foot towers, I have usually wanted to swing a monobander around
the tower at some mid-point so I usually was putting in wider guy spacing
than would be nominal for many hams). Also, I have never used a pier pin. I
have always used a short base section into the concrete and then tower on
top of the imbedded short section.
I always started the tower thusly....
I assembled the short tower section and one 10' section and put those two
sections in the hole for the concrete. I used lite ropes to hold this
vertical as we poured concrete. The bottom of the whole had the bottom legs
slightly immersed into course gravel. Pour the concrete and let cure for a
week or more. Then, I would routinely stack three more full 10' sections of
tower on top of the base 10' section already installed along with the short
base (Rohn 45). No guys at all. On the 90 footers and 75' (rohn 25), I would
sometimes guy about 35' as the first guy (40' of tower was mounted before
the first set of guys were placed. On my hundred footers, I would guy only
twice at mid-point (45') and again at 90' (I left 5 to 10' unguyed at the
top so that the guy brackets and hardware were not right at the top of the
tower. This would mean on Rohn 45, that I would stack a total of 50' of
tower before it was guyed. With Rohn 45, this was NEVER scary or a problem.
Rohn 45 will take 50' with a man on gin-pole on the tower with no excessive
sway or problem (to stack 50' of tower, you only need a man at 40', but we
would then move up to about 45' on the tower before we would . Rohn 25 is
less solid and needs to be guyed more, but even with my very first tower
(Rohn 25) at 78', I guyed it three times at roughly equal intervals. By and
large, I followed Rohn guidelines and did my concrete and guy brackets
according to Rohn spec.
If you are still at the planning stage, let me pass along one other piece of
advice. The difference between Rohn 25 and Rohn 45 for comfort while working
on the tower and the comfort of the climber while climbing and working on
the tower and antennas is no comparison.... I will never again use Rohn 25
(actually I have sold all of it) and the additional money invested in Rohn
45 is very well worth the expenditure. On Rohn 45, everything just is easier
for the man on the tower and climbing. In addition, it is two or three times
as rigid and solid as Rohn 45. Even if I was putting up a relatively small
VHF array, I would none-the-less spend the extra money and use Rohn 45 if I
could afford it, simply for the comfort of the man working on the tower and
servicing the antennas. Once you use Rohn 45 you will never think of 25
again..
OH, and I was routinely 200 - 250 pounds during all those construction
projects.
Good luck
Gary W5FI
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of Larry Boekeloo
Sent: Thursday, April 09, 2009 8:11 PM
To: towertalk@contesting.com
Subject: [TowerTalk] Guyed tower question
I'm thinking about putting up a Rohn 25 or 45 tower to at least 60 feet.
What does one use as temporary guys while building the tower? Do you put
temporary guys on each section as you go and keep moving them upwards?
Thanks.
Larry, KN8N
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