Mike,
An interesting setup for sure. To be honest, with a guyed setup, you
shouldn't need much of a base if you are on solid ground. I have been
convinced by numerous people to use a pier pin assembly with the Rohn BPC25G
base plate on top of a concrete pier. The rationale behind this as opposed
to a section embedded in concrete is that as there are rotational moments on
the tower, the base is free to move slightly. With a fixed base in
concrete, all twisting forces are taken up in the tower itself. The only
thing the pin does is to keep the tower on the concrete pad. Makes sense to
me and made pouring the concrete, etc. a lot easier. To me, the pier is
probably much bigger than needed for this setup (2'x2'x4') but it is
certainly solid. Yes, you need guys all the time, but you are going to have
them anyhow....
73,
Jon
NA9D
on 9/4/02 8:20 PM, Mike Wetzel at mjwetzel@comcast.net wrote:
> Jerry,
>
> My wood bases are comprised of 2- 6" x 6" x 4' long treated pieces of wood
> covered with asphalt roofing compound. The pieces are laid horizontally
> together, a Rohn base plate is attached to the wood with long lag screws and
> on 2 diagonal corners of the pieces I have drilled holes and drove 1" steel
> pipes into the ground. That's about all I remember about them because my
> dad and I did this in about 1975. Obviously you can only put one section up
> before you have to guy it temporarily to add more sections. With the 4' of
> surface area, I have not noticed any sinking although I'm sure there must
> have been some over the last 27 years. They probably won't last forever,
> but.
>
> As I've said here before, I have no concrete on any of my guy anchors. For
> the Rohn 25 towers just screw in anchors and truck driven 10" anchors on my
> Rohn 45 (170') and 55 (150') towers.
-------------------------------------
Jon Ogden
NA9D (ex: KE9NA)
Life Member: ARRL, NRA
Member: AMSAT, DXCC
http://www.qsl.net/ke9na
"A life lived in fear is a life half lived."
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