I am certainly not an expert in this area but I will give you my ideas in
order to maybe generate some comments from someone more knowledgeable than
I. As I understand it the create roof tower is designed not to use guys.
Putting guys on this tower it seems to me would just increase the downward
load on the roof and tower. This could cause premature failure. The whole
design rests on the strength of the roof and how securely you can attach the
base of the tower to the roof. If you fail to calculate this properly you
will tear your roof off. The reason everyone got so upset when you were
going to add a 15 ft mast is this just increases the lever and if your tower
does not collapse you will tear your roof off sooner! If you guy it and the
tower survives then you will punch a large hole in your roof. You need to
calculate the loads and understand your roof's strength. I don't know how to
do this. Even if I did I would have to know the characteristic of your roof
construction. I hope this helps some.
73 Steve W8GAZ
-----Original Message-----
From: WBH3@chrysler.com <WBH3@chrysler.com>
To: towertalk@contesting.com <towertalk@contesting.com>
To: <towertalk@contesting.com>
Date: Friday, August 14, 1998 1:32 PM
Subject: [TowerTalk] Torque bars for Create CR-45 Tower-----REVISITED
>
>
>I really needed some help on this and was ....well.....very disappointed
>that I got only 2 comments back on my questions. Both comments basically
>said ....FORGET IT!
>
>I have reconsidered and am now going to put my KT34XA about 1 foot above
>the tower. I STILL NEED SOME ADVICE on the feasibility of this project
>and any construction hints relating to the home-brewing of torque bars for
>this square tower. Are my ideas unsound? Is the KT34XA just plain TOO big
>to put on this kind of a tower? Does anyone have experience or knowledge
>of someone who has attempted this scenario? Please ignore the comments
>about putting the antenna 5 feet above tower.................My initial
>posting follows:
>
>
>---------------------- Forwarded by William B Haselmire/SCI/Chrysler on
>08/14/98 12:29 PM ---------------------------
>
>
>William B Haselmire
>08/06/98 09:54 AM
>
>To: towertalk@contesting.com
>cc: bg@tir.com
>Subject: Torque bars for Create CR-45 Tower
>
>Greetings all:
>Actually, I have a whole bunch of questions related to the Create tower
>installation I am doing on the 2nd. story of my house. This particular
>tower is almost 15 feet tall with a base section one meter on a side. The
>tower necks down to about 7 inches square at the top. I have no problems
>getting the thing mounted securely on my roof, but I am worried about a
>couple of things:
>
> 1.I plan to put up my KLM KT34-XA. I'm buying a 15 foot mast , 0.12
>" wall and 87000 psi., from Texas Towers. Now the rotator mounting plate
>is at the 10 foot level of the tower, so I will have 9 feet sticking out
>of the top of the tower. I plan to put the KT34 5 feet above the tower
>(and thrust bearing) and the boom support bracket will be about 3 feet
>above that. So, question 1, am I being a little bit over optimistsic
>putting the beam that far above the tower? I really don't want to put it
>just a foot above the tower,. I do plan to put a piece of reinforcing
>metal on the very top of the tower for structural support. I also plan to
>put some bracing between the sides of the the tower at 2 different levels
>also.
>
>2.Since the KT34 -XA has a 30 foot boom, I want to provide some torque bars
>to help things along. The tower is square and will be guyed 5 feet up and
>15 feet upl The guys will obviously be at 45 degrees to the sides of the
>tower. I had thought about putting steel angle iron along each edge of
>the tower and about 18 inches out and then guying to that.
>
>Another idea is to put a plate on top of the tower, bend the corners down
>about 60 degrees and secure a strong hasp to the corners and the other end
>of the hasp to an aluminum bar about 18 inches long and guy to that. (this
>seems to be a better idea in my mind). Any other ideas or comments??
>I'll be using Phillystran at 1200 lbs strength.
>
>I'm putting 8 - inch long feet on each leg, each made out of 2 inch angle
>aluminum a quarter inch thick. The legs will be anchored through the roof
>with two lengths of 1/2 inch threaded rod to a 2 by 6 attached to the roof
>joists. The guying points will be half inch threaded rod with a welded 1
>inch eye also going through the roof into a 2 by 6 nailed between the roof
>joists (which are on 2 foot centers). The roof is only one half inch chip
>board and seems to be the weakest link here.
>
>I realize the KT34-XA is a pretty big antenna but it has been a super
>performer for me and I sure hate to downsize! On the other hand, with the
>expertise on this reflector, I am sure I'll find out if I am being too
>aggressive.
>
>Thanks and 73,
>
>Bill WX8S
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