No one has answered my question about the Mobile home
Can you bracket to the V at the side of a mobile home or will the mobile home
hold it?
It is a rental and I have permission for antennas, but wouldn't want to pay for
a new wall or anything :)
tnx Bob AD5VJ
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of Jim Jarvis
> Sent: Thursday, November 15, 2007 1:58 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] unguyed with house bracket
>
>
> Lest the critical info be lost, there was a post which
> referred the Uninitiated to a QST article on how to
> house-bracket correctly.
>
> Fascia boards are trim, not structure. You must tie into the
> structure.
>
> Using a 2x6 backing plate inside an attic sidewall is preferred.
> But here's an alternative which has worked:
>
> I did not have an attic, it was a flat-roofed house. All I
> could do Is lag screw into the roof joists and the floor
> joists between the first and second floors. That gave me two
> points of attachment.
>
> My 'bracket' was constructed of 2x8's, 5' long, which spanned
> 3 bays of Roof joists. I used 1/2" x 12" lag screws into the
> 2x12 roof joists, Carefully locating their centers, and
> pre-drilling pilot holes, so nothing split. There were 2
> bolts at each of the 3 joists I intersected. Each bolt was
> rated for 2700 lbs extraction force, and considerably more in shear.
>
> The tower was captured by a sandwich of 2x6"s which were
> bolted to the 2x8 backing beams in question. So, I had the
> ability to withstand something
> >12,000 lbs pullout, and 24,000 lbs shear failure at each of the two
> brackets.
>
> In turn, I calculated the windload with ice, from the
> antennas and tower, and determined that at 90mph, it should
> be no more than around 5,000 lbs at the point of the upper
> bracket. With a more than 2x safety margin, I felt
> reasonably comfortable.
>
> Let me point out that there were critical measurements
> involved, and that a borescope was used to look at each pilot
> hole...and that each lag screw was installed, removed, the
> hole inspected for structure, and reinstalled.
> You can't be casual about whether you've hit the beam or not,
> in that situation.
>
> And NO, you can't rely on a double-wide at 10' to hold up a
> tower at 40', with any kind of wind. You don't have the
> overbuilt structure that is common with site-built houses.
>
> n2ea
>
>
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