I am in the process of installing the same identical tower at my QTH. Guy
wire tension is determined by the size of the guy wire. In the case of EHS
3/16 specified by Rohn for this tower, the tension is 10% of the breaking
strength which is specified at 3900 lbs. This is the value for guys at 80%
of the tower height away from the base. The Rohn manual for this tower
specifies a distance of 25'. from the base which is 80%. It is also
recommend that Big End cable grips be used on the guy wire ends as opposed
to cable clamps. Which base are you going to use? I am considering a hinged
base plate as opposed to the imbedded tower section which would allow me to
assemble the 31" section on the ground and two people could walk it up to
vertical. I have assembled the upper 26' section on the ground and it is
separated at the hinge bolt. I will hire a bucket truck to lift it into
position and then install the hinge bolt.
The manuals that I have found for this tower show two different
configurations for the boom section. Mine is a welded frame work while
another manual also shows a solid bar type boom section. The drawing for
this mast is attached. I also have pdf copies of the Rohn manuals for the
tower.
Palmer Byrne
W7NMD
On Sat, Jul 9, 2011 at 3:03 PM, Robb Urie <rurie@mywdo.com> wrote:
> Hello,
>
> In the process of replacing a 50 foot Rohn 25G with a 58 foot fold over
> version. New base and guy wire anchors have been poured and the question
of
> guy wire tension needs clarification. Neither one of my Rohn catalogs
> mention anything specific regarding the tension for the 4 guy wire scheme
> vs.
> the 3 found on conventional installs. I?m wondering if using the standard
> formula of 10% tension will still be okay even with the extra guy wire.
> Will
> be using new 3/16 EHS and hardware and have a Loos PT-2 tension gauge. If
> anyone out there knows of any mention of the proper tension with the
> fold over kits, I?d certainly appreciate it. Also, any owners with
> interesting ideas of lifting the boom assembly would be valuable. My plan
> was to use
> my trusty tower assistant; Mr. ATV and gin pole.
>
> Any info or thoughts can be sent direct to: rurie@mywdo.com
>
> Thanks,
>
> Robb N?RU
> Woodland Park, CO
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