[TowerTalk] bracketed 45G

[Jim Jarvis]

fwd'd to reflector, because it's a relevant question:

I wrote:

> If your structure has deep eaves, you'll be
> stuck with using the Rohn house bracket.  I found that to be more
> flexible than I wished, which drove me to design my own.  
>   
Bud, W2RU, wrote:

Gee, I wonder if you're thinking of the "older" Rohn brackets?  Compared 
to the Rohn house brackets I bought a few decades ago for my Rohn 25 
towers, the Rohn house brackets I bought six years ago for my Rohn 45 
tower are *massive* and about as flexible as a cinder block.
-0-
expanded comments:

Bud...I dunno.  May well be.  The ones I saw only 
intersected two joists, not 3, and they extended out
from the building by 22".   I wanted more tie-in to
the structure.  

Wiggle, by itself, is a GOOD thing.  It dissipates
impulse loads on the structure.  So I wasn't totally against
the rohn brackets.  My personal problem was lack of access to
the roof and floor joists-- I had to lag-screw into them, 
rather than using backing plates.  That's why I wanted to tie into
more joists.  Being closer to the building was an aesthetic consideration.

Now that I think about it, my impression was formed by a 25G
bracket I had in an earlier installation, not a 45G bracket.
The latter may be considerably more rigid.  But still 36" wide,
and not 48...which was a personal requirement. 

For the chap who originally asked, however, I believe he's still
constrained by the available engineering data and code compliance
requirements.  Gotta use the mfr's data.

N2EA 


-----Original Message-----
From: W2RU - Bud Hippisley [mailto:W2RU at frontiernet.net]
Sent: Thursday, June 15, 2006 10:28 PM
To: Jim Jarvis
Cc: towertalk at contesting.com
Subject: Re: bracketed 45G


Jim Jarvis wrote: