Tower project

I'm in beginning stages of installing a 50' guyed Glen Martin tower, 13"
per side.
http://www.glenmartin.com/catalog/page6.html
Finished digging the 45" cube hole for the concrete base yesterday.
Quite a chore with a small hand shovel, but kept thinking about the
"Little Engine that could, "I think I can, I think I can... Started out
with a larger shovel, but the small 'stricker' type was just right at
depth and what I could lift up to the wheel barrow. Soil is a dirt-clay
mix. I figure it took about 18 hours, a couple hours at a time over a
week, since I'm an old geezer.

Next step is to secure the tower base, which consists of 3 28" 3/4"
rods, secured at their top and bottom with metal braces, that will match
the tower base. I'm working on how to secure it in place while concrete
is poured. Thinking of rebar into the dirt sides and bottom corners,
tied securely to the base with wire.

Any better ideas or suggestions?

trees

Any reason I shouldn't use two old healthy 40'+ oak trees as guy
supports from about the bottom 4-5' of the trees? I have three supplied
ground 'screw in' guy anchors, but these trees are in the right place
and I couldn't screw in the ground anchors with so many big tree roots
in the vicinity. Maybe use very large and long screw eye-bolts, or
possibly drill a hole for a bolt through the 15" dia trunk?

The tower and beam will be well grounded. Does it matter if guy wires
are also grounded, or not?

House and 3rd guy

The tower will be about 3-6' from the house and I have a heavy duty
house bracket that could go into a window header 2 x 6 about 8' above
ground. I know it's not necessary, and I have no idea how secure the
header is, but I figure it'd help keep it stable, esp when several guys
would be lose while raising the hazar platform which contains the rotor
and mast while moving it and my beam up the tower and above the top guy
wire brackets. I'll be able to assemble the beam onto the mast while
standing on my 1-story house.

The tower itself, being HD aluminum and about 220 lbs, is to be walked
up by a few good men via the base's hinge plate.

Would like to hear "words of wisdom" from anyone who's worked on a
similar tower project.

TNX

Marv W5MTV

Stupid idea. Trees grow and thus move over time. They're not stable long
enough for construction purposes.

On Sat, 28 Feb 2009 17:41:22 -0600, MTV
wrote:

The tower and beam will be well grounded.

Hi Marv,

Take advantage of an excellent opportunity to create an "Ufer Ground."

In a nutshell, when you put in the rebar, weld each piece to the
others for continuity, and then make provision for a wire (either
securely clamped, or likewise welded) connection to the assembly that
is accessible for further connection outside of the block of concrete.
This wire will be a low Ohmic ground lead.

possibly drill a hole for a bolt through the 15" dia trunk?

This should be robust, but think carefully about how those guys span
out towards the trees. If they are not dead-on in angle away from the
tower (as a function of their tower connection) you may twist the
tower and weaken it.

I have no idea how secure the header is

Will that statement go into an insurance claim? Houses are not built
for lateral strength. Not only does the wall lack the stiffness of
your Oak trees, it is far closer to the moment arm (think crowbar).

73's
Richard Clark, KB7QHC

On Sat, 28 Feb 2009 17:41:22 -0600, MTV
wrote:

Tower project


trees

Any reason I shouldn't use two old healthy 40'+ oak trees as guy
supports from about the bottom 4-5' of the trees? I have three supplied
ground 'screw in' guy anchors, but these trees are in the right place
and I couldn't screw in the ground anchors with so many big tree roots
in the vicinity. Maybe use very large and long screw eye-bolts, or
possibly drill a hole for a bolt through the 15" dia trunk?

As the tree trunk grows and expands, it will swallow up the eye bolt!

bob
k5qwg

Would like to hear "words of wisdom" from anyone who's worked on a
similar tower project.

TNX

Marv W5MTV

On Sat, 28 Feb 2009 16:53:38 -0800, D. Stussy wrote:

Stupid idea. Trees grow and thus move over time. They're not stable
long enough for construction purposes.

Mark a spot 4-5 feet up on a tree, 20 years later it will still be 4-5
feet from the ground.

73's
Ken Slimmer, WA0SBU

In message , Ken Slimmer
writes
On Sat, 28 Feb 2009 16:53:38 -0800, D. Stussy wrote:

Stupid idea. Trees grow and thus move over time. They're not stable
long enough for construction purposes.

Mark a spot 4-5 feet up on a tree, 20 years later it will still be 4-5
feet from the ground.

But won't the diameter, where you marked, be a lot greater? Anything
tied to the tree will get buried in the wood. Even if you leave 'room
for expansion', this may still happen. A tight loop, buried in the wood,
will also choke off the sap, and possibly kill the part of the tree
above.
--
Ian

Ken Slimmer wrote:
On Sat, 28 Feb 2009 16:53:38 -0800, D. Stussy wrote:

Stupid idea. Trees grow and thus move over time. They're not stable
long enough for construction purposes.

Mark a spot 4-5 feet up on a tree, 20 years later it will still be 4-5
feet from the ground.

73's
Ken Slimmer, WA0SBU

Bad idea, trees move in the wind even big ones close to the ground. That
puts a lot of extra strain on the tower. If the tree blows over so does
your tower and trees blow over more often than towers. Also it's bad for
the tree and can kill it then it's an even worse guy anchor. I've seen
it done and by people who should have known better and it came to a bad end.
My ham club salvaged some nice hard line off the wreckage though.


John Passaneau W3JXP

"Ian Jackson" wrote in message
...

snip

Mark a spot 4-5 feet up on a tree, 20 years later it will still be 4-5
feet from the ground.

But won't the diameter, where you marked, be a lot greater? Anything
tied to the tree will get buried in the wood. Even if you leave 'room
for expansion', this may still happen. A tight loop, buried in the wood,
will also choke off the sap, and possibly kill the part of the tree
above.

I think maybe you could drill a hole through the tree with a wood borer.
The Irwin Speedbor toolset comes to mind. They can be fitted with
extensions for added length. I have two, 6" & 12". They use setscrews to
avoid the bulk of a chuck. Love 'em.

http://www.irwin.com/irwin/consumer/...brand=Speedbor

After the hole is through, slide in a piece of All-Thread, flange it with
some sheet aluminum (and maybe a couple of rubber bumpers to be a little
kinder to the bark) and add nuts. Attach your guy wire to the protruding
end of the All-Thread.

Trees will tolerate being drilled. I mounted a garden hose rack on a tree
about 20 years ago; tree and hose rack still doing fine as of this
afternoon.

================

I didn't see this mentioned: Have you investigated the possible use of a
concrete "deadman anchor"?

On Sun, 01 Mar 2009 23:39:07 -0500, John Passaneau wrote:

Ken Slimmer wrote:
On Sat, 28 Feb 2009 16:53:38 -0800, D. Stussy wrote:

Stupid idea. Trees grow and thus move over time. They're not stable
long enough for construction purposes.

Mark a spot 4-5 feet up on a tree, 20 years later it will still be 4-5
feet from the ground.

73's
Ken Slimmer, WA0SBU

Bad idea, trees move in the wind even big ones close to the ground. That
puts a lot of extra strain on the tower. If the tree blows over so does
your tower and trees blow over more often than towers. Also it's bad for
the tree and can kill it then it's an even worse guy anchor. I've seen
it done and by people who should have known better and it came to a bad
end. My ham club salvaged some nice hard line off the wreckage though.


John Passaneau W3JXP

Hi John;
I wasn't advocating the use of trees as Guy supports for a tower.
They work great as supports for wire antennas. My Boxelders and Oaks
that are 2-3 feet across hardly move in a strong wind. And, no, putting
Eye bolts in a mature tree will not kill it.



--
73's
Ken Slimmer, WA0SBU

On Sun, 01 Mar 2009 20:28:42 +0000, Ian Jackson wrote:

In message , Ken Slimmer
writes
On Sat, 28 Feb 2009 16:53:38 -0800, D. Stussy wrote:

Stupid idea. Trees grow and thus move over time. They're not stable
long enough for construction purposes.

Mark a spot 4-5 feet up on a tree, 20 years later it will still be 4-5
feet from the ground.

But won't the diameter, where you marked, be a lot greater? Anything
tied to the tree will get buried in the wood. Even if you leave 'room
for expansion', this may still happen. A tight loop, buried in the wood,
will also choke off the sap, and possibly kill the part of the tree
above.

Ian;
We have used trees as supports for barbed wire by wrapping it around
the tree. The tree just grew over it, healing itself as it grew around
it.



--
73's
Ken Slimmer, WA0SBU