John, if I was in your shoes I would drop the idea of a guyed tower
installed with guying as you describe. It will be a real headache to get
it approved. I would go the self supporting tower route. It would be
much more attractive. You could use HDBX Rohn or one of the nice
Canadian jobs that Steve sells. Maybe R45 might work unguyed. Am I
missing something?
73, Dan, N5AR
John Parnell wrote:
> Hello!
>
>
>
> This is my first post to this list; my apologies for the lonnng post… I am
> building a tower for myself the first time in 23 years. I have worked for
> my friend Steve, K7LXC/Towertech helping with many of his installations over
> the years. I have done quite a bit of research at the Rohn site and found
> some excellent resources here on the web ; I am eagerly awaiting the arrival
> of Steve’s tower book…
>
>
>
> I have one nagging question that I am having a hard time answering, I
> attempted to search the archives here and the www in general, but could not
> spot anything that related to this issue.
>
>
>
> My installation is a simple one: 40 ft of Rohn 25G ; it will have a yard
> of concrete for a base covering the bottom four feet of tower. It will go up
> THROUGH an existing deck at five feet- I will bolt it to a header I will
> install as it goes through the deck. I will also have a Rohn house bracket
> installed at the 15ft level , with a sturdy backup structure (as per K1KP &
> N1CQ’s excellent QST article of 8/96). There will be a five foot mast
> holding an ancient Wilson SY33 yagi (TA33 clone)with 5.9 sq ft wind load.
> >From what I can tell from the Rohn specs, I will still need to guy the tower
> since it will have aprox 21 ft of structure above the bracket.
>
>
>
> My question concerns guy anchors:
>
>
>
> My fiancé says it would be fine to guy to the roof but NOT out into her yard
> to anchor guys to the ground in her nicely landscaped yard. There is plenty
> of room to mount guys on the roof 32 ft back from the tower in 3 places ( I
> am foggy on this point, I am not sure if I should calculate the height of
> the tower from the bracket or base for guying purposes; I could do either)
>
>
>
> My problem is that I need to know the best way to anchor the guys to the
> roof. My guess is that the best way would be to put a large diameter eye
> bolt down through the roof to the top plate of the wall at a corner, or -
> next to an intersecting interior wall and through-bolt it with a nuts and
> washers (or a flat bar). This would be a BIG problem in that I would have to
> dig through a lath and plaster wall…it would be ugly. What I would LIKE to
> do is place a piece of heavy angle iron (3x3x1/4?) UNDER the rafter tails of
> the eaves just outboard of the wall. I would then run the eye bolt through
> the roof and and secure it under the center point of the angle. I could
> further beef this up by crawling into the attic and bracing the affected
> rafters to the ceiling joists below. I could also anchor it to the peak of
> the roof by adding a bit of backup structure.
>
>
>
> Complicating this is the need to get a city permit for the installation;
> whatever I come up with needs to be kosher with an engineer; Has anyone
> here had experience with roof mounted guy anchors that have passed muster
> with a professional engineer? Any ideas/suggestions greatly appreciated. I
> am a former welder/steel fabricator with a welding machine and could make
> what I need add structure where needed. Also, if any of you are in the
> Seattle area and know of a Ham-friendly prof. engineers, email me off-list.
>
>
>
> Thanks!
>
>
>
> -John, K7HV
>
> _______________________________________________
>
>
>
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