On 12/20/2010 04:13 PM, stryped wrote:
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

There are a lot of different tower types, 3 sided, 4 sided, steel,
aluminum, tapered, straight... And within those, there are different
sizes, depending on how much antenna and how tall. If you can figure out
who made your tower, it will help you find stuff that would work with it.

There is a lot of tower stuff available in the ham radio world. If you
have the right size tower for this particular unit would be a piece that
uses the tower tubes a guides and rides up and down the tower with a
rope: http://www.texastowers.com/glenmartin_hazer.htm. Texas Towers has
quite a bit of tower related hardware. Another vendor that has a lot of
tower hardware is: WWW.DXENGINEERING.com. Another one is:
WWW.mfjenterprises.com. If nothing else, you might get some ideas on
what is being done.

Good Luck,
BobH

I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

"stryped" wrote in message
...
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

I have considered similar for raising owl boxes, and raptor perches. My
thoughts come down to three pad eyes, the center one being on the base of
the tower, the other two, set into a concrete base, all three match drilled
through, and secured by a heavy bolt. A pad eye is a D shaped piece of
metal, but can be long, with the hole drilled in the D. You've seen them as
lifting points on machinery. The one on the base of the tower would fit
between the two set in the concrete.

Lifting and lowering would have to be done with a winch or a vehicle, and a
three point guy system would make it steady.

Lowering the antenna in the first place for installation of the hinge part
would be the biggest process.

Raising would consist of leaving the two guy wires in place, and pulling on
the third, but using some sort of helping member to make the pulling cable
pull upward slightly rather than just horizontally. The two permanent guy
wires would hold the antenna safely in place while lowering and raising with
the third detachable one, once you have them to the correct length.

It would be some work at first, but then very easy to raise or lower it.
Align the hinge to bisect the line of the two stationary guy wires, and the
third perpendicular to that on the other side, all the same length. They
could be all the way to the top, or just 2/3 of the height, and be steady.

Take some pictures and share. Perhaps someone who has BTDT can give you
better advice, or another way if you post some pics.

Steve

Steve B wrote:

"stryped" wrote in message
...
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

I have considered similar for raising owl boxes, and raptor perches. My
thoughts come down to three pad eyes, the center one being on the base of
the tower, the other two, set into a concrete base, all three match drilled
through, and secured by a heavy bolt. A pad eye is a D shaped piece of
metal, but can be long, with the hole drilled in the D. You've seen them as
lifting points on machinery. The one on the base of the tower would fit
between the two set in the concrete.

Lifting and lowering would have to be done with a winch or a vehicle, and a
three point guy system would make it steady.

Lowering the antenna in the first place for installation of the hinge part
would be the biggest process.

Raising would consist of leaving the two guy wires in place, and pulling on
the third, but using some sort of helping member to make the pulling cable
pull upward slightly rather than just horizontally. The two permanent guy
wires would hold the antenna safely in place while lowering and raising with
the third detachable one, once you have them to the correct length.

It would be some work at first, but then very easy to raise or lower it.
Align the hinge to bisect the line of the two stationary guy wires, and the
third perpendicular to that on the other side, all the same length. They
could be all the way to the top, or just 2/3 of the height, and be steady.

Take some pictures and share. Perhaps someone who has BTDT can give you
better advice, or another way if you post some pics.

Steve

There are a lot of ways to do it and a lot of types of towers that
dictate the correct way to do it for that tower. Honestly, 25' is an
extremely short tower so climbing it really shouldn't be a concern. Just
buy the correct safety harness and "Y" 100% tie-off lanyard (~$100 or so
total) and get on with it with far less hassle than trying to
re-engineer the tower.

Pete C. wrote:
Steve B wrote:

"stryped" wrote in message
...
I have an antenna tower in concrete behind my garage that has my
local tv station antenna. It is a big yagi type antenna. It has
been there, both the antenna and tower, for 12 years. I am getting
a little older and dont have any help and to be honest, dont like
climbing up it. I think the tower is 25 feet ot so from it's top to
the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to
install the hinge. I appreciate any help.

I have considered similar for raising owl boxes, and raptor perches.
My thoughts come down to three pad eyes, the center one being on the
base of the tower, the other two, set into a concrete base, all
three match drilled through, and secured by a heavy bolt. A pad eye
is a D shaped piece of metal, but can be long, with the hole drilled
in the D. You've seen them as lifting points on machinery. The one
on the base of the tower would fit between the two set in the
concrete.

Lifting and lowering would have to be done with a winch or a
vehicle, and a three point guy system would make it steady.

Lowering the antenna in the first place for installation of the
hinge part would be the biggest process.

Raising would consist of leaving the two guy wires in place, and
pulling on the third, but using some sort of helping member to make
the pulling cable pull upward slightly rather than just
horizontally. The two permanent guy wires would hold the antenna
safely in place while lowering and raising with the third detachable
one, once you have them to the correct length.

It would be some work at first, but then very easy to raise or lower
it. Align the hinge to bisect the line of the two stationary guy
wires, and the third perpendicular to that on the other side, all
the same length. They could be all the way to the top, or just 2/3
of the height, and be steady.

Take some pictures and share. Perhaps someone who has BTDT can give
you better advice, or another way if you post some pics.

Steve

There are a lot of ways to do it and a lot of types of towers that
dictate the correct way to do it for that tower. Honestly, 25' is an
extremely short tower so climbing it really shouldn't be a concern.
Just buy the correct safety harness and "Y" 100% tie-off lanyard
(~$100 or so total) and get on with it with far less hassle than
trying to re-engineer the tower.

25'? try a tall ladder and a teenager.

chaniarts wrote:
Pete C. wrote:
Steve B wrote:

"stryped" wrote in message
...
I have an antenna tower in concrete behind my garage that has my
local tv station antenna. It is a big yagi type antenna. It has
been there, both the antenna and tower, for 12 years. I am getting
a little older and dont have any help and to be honest, dont like
climbing up it. I think the tower is 25 feet ot so from it's top to
the ground.

Would it be possible to make a hinge for this thing so I could
bring it down to replace the anteena? Can I do it now that it is
already errected, maybe loosening at one of the sections and
pulling it off, installing the made hinge then putting back on?
Would I be able to lift the tower and antenna by myself once it is
pulled off to install the hinge. I appreciate any help.

I have considered similar for raising owl boxes, and raptor perches.
My thoughts come down to three pad eyes, the center one being on the
base of the tower, the other two, set into a concrete base, all
three match drilled through, and secured by a heavy bolt. A pad eye
is a D shaped piece of metal, but can be long, with the hole drilled
in the D. You've seen them as lifting points on machinery. The one
on the base of the tower would fit between the two set in the
concrete.

Lifting and lowering would have to be done with a winch or a
vehicle, and a three point guy system would make it steady.

Lowering the antenna in the first place for installation of the
hinge part would be the biggest process.

Raising would consist of leaving the two guy wires in place, and
pulling on the third, but using some sort of helping member to make
the pulling cable pull upward slightly rather than just
horizontally. The two permanent guy wires would hold the antenna
safely in place while lowering and raising with the third detachable
one, once you have them to the correct length.

It would be some work at first, but then very easy to raise or lower
it. Align the hinge to bisect the line of the two stationary guy
wires, and the third perpendicular to that on the other side, all
the same length. They could be all the way to the top, or just 2/3
of the height, and be steady.

Take some pictures and share. Perhaps someone who has BTDT can give
you better advice, or another way if you post some pics.

Steve

There are a lot of ways to do it and a lot of types of towers that
dictate the correct way to do it for that tower. Honestly, 25' is an
extremely short tower so climbing it really shouldn't be a concern.
Just buy the correct safety harness and "Y" 100% tie-off lanyard
(~$100 or so total) and get on with it with far less hassle than
trying to re-engineer the tower.

25'? try a tall ladder and a teenager.

the mast of my catamaran is shorter than that. it has a base hinge. a couple
of guy wires attached to a pair of small boat trailer winches, a pair of
mast base hinges, and releasable pins on the other legs would do this.

On Dec 20, 11:13*am, stryped wrote:
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. ...

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

It shouldn't be too hard but when you do it you need experienced hands-
on advice in person, not from the Internet. My 50 foot antenna mast
hinges down.

If the tower unbolts at the base you can hinge it there. Higher up the
hinge and lowest tower section will be pushed very hard sideways when
you lower the tower with a rope.

jsw

On Dec 20, 11:11*am, "chaniarts" wrote:
Pete C. wrote:
Steve B wrote:

"stryped" wrote in message
....
I have an antenna tower in concrete behind my garage that has my
local tv station antenna. It is a big yagi type antenna. It has
been there, both the antenna and tower, for 12 years. I am getting
a little older and dont have any help and to be honest, dont like
climbing up it. I think the tower is 25 feet ot so from it's top to
the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to
install the hinge. I appreciate any help.

I have considered similar for raising owl boxes, and raptor perches.
My thoughts come down to three pad eyes, the center one being on the
base of the tower, the other two, set into a concrete base, all
three match drilled through, and secured by a heavy bolt. *A pad eye
is a D shaped piece of metal, but can be long, with the hole drilled
in the D. *You've seen them as lifting points on machinery. *The one
on the base of the tower would fit between the two set in the
concrete.

Lifting and lowering would have to be done with a winch or a
vehicle, and a three point guy system would make it steady.

Lowering the antenna in the first place for installation of the
hinge part would be the biggest process.

Raising would consist of leaving the two guy wires in place, and
pulling on the third, but using some sort of helping member to make
the pulling cable pull upward slightly rather than just
horizontally. *The two permanent guy wires would hold the antenna
safely in place while lowering and raising with the third detachable
one, once you have them to the correct length.

It would be some work at first, but then very easy to raise or lower
it. Align the hinge to bisect the line of the two stationary guy
wires, and the third perpendicular to that on the other side, all
the same length. *They could be all the way to the top, or just 2/3
of the height, and be steady.

Take some pictures and share. *Perhaps someone who has BTDT can give
you better advice, or another way if you post some pics.

Steve

There are a lot of ways to do it and a lot of types of towers that
dictate the correct way to do it for that tower. Honestly, 25' is an
extremely short tower so climbing it really shouldn't be a concern.
Just buy the correct safety harness and "Y" 100% tie-off lanyard
(~$100 or so total) and get on with it with far less hassle than
trying to re-engineer the tower.

25'? try a tall ladder and a teenager.- Hide quoted text -

- Show quoted text -

To be honest, I dont like hights.

I wondered if I could make a steel base with three pieces of tube
bigger than the tube on the tower that would fit into the new tubes if
that makes sense. My tower is the three sided stuff and I think it is
steel but it may be aluminum. It is gray colored.

Also, it is hard to climb up it with a 10 foot long antenna in your
hand.

On Dec 20, 11:18*am, Jim Wilkins wrote:
On Dec 20, 11:13*am, stryped wrote:

I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. ...

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

It shouldn't be too hard but when you do it you need experienced hands-
on advice in person, not from the Internet. My 50 foot antenna mast
hinges down.

If the tower unbolts at the base you can hinge it there. Higher up the
hinge and lowest tower section will be pushed very hard sideways when
you lower the tower with a rope.

jsw

My tower is up againts the back of the garage with nothign else nearby
really. I do have an attic area above the garage. What i made a braket
out of angle iron with a pulley, atteched the braket to a couple of
studs through the attic wall. I have brick around my garage footer/
foundation. COuld I mound a hand crack winch directly into the brick/
block with concrete screws. Then run the winch rope/cable up through
the pulley and attaching the middle or top part of the mast. With a
hinge at the bottom of the tower, I could use the winch to raise lower
the mast? Just thinking out loud.

On Mon, 20 Dec 2010 09:22:19 -0800 (PST), stryped
wrote:

On Dec 20, 11:11*am, "chaniarts" wrote:
Pete C. wrote:
Steve B wrote:

"stryped" wrote in message
...
I have an antenna tower in concrete behind my garage that has my
local tv station antenna. It is a big yagi type antenna. It has
been there, both the antenna and tower, for 12 years. I am getting
a little older and dont have any help and to be honest, dont like
climbing up it. I think the tower is 25 feet ot so from it's top to
the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to
install the hinge. I appreciate any help.

I have considered similar for raising owl boxes, and raptor perches.
My thoughts come down to three pad eyes, the center one being on the
base of the tower, the other two, set into a concrete base, all
three match drilled through, and secured by a heavy bolt. *A pad eye
is a D shaped piece of metal, but can be long, with the hole drilled
in the D. *You've seen them as lifting points on machinery. *The one
on the base of the tower would fit between the two set in the
concrete.

Lifting and lowering would have to be done with a winch or a
vehicle, and a three point guy system would make it steady.

Lowering the antenna in the first place for installation of the
hinge part would be the biggest process.

Raising would consist of leaving the two guy wires in place, and
pulling on the third, but using some sort of helping member to make
the pulling cable pull upward slightly rather than just
horizontally. *The two permanent guy wires would hold the antenna
safely in place while lowering and raising with the third detachable
one, once you have them to the correct length.

It would be some work at first, but then very easy to raise or lower
it. Align the hinge to bisect the line of the two stationary guy
wires, and the third perpendicular to that on the other side, all
the same length. *They could be all the way to the top, or just 2/3
of the height, and be steady.

Take some pictures and share. *Perhaps someone who has BTDT can give
you better advice, or another way if you post some pics.

Steve

There are a lot of ways to do it and a lot of types of towers that
dictate the correct way to do it for that tower. Honestly, 25' is an
extremely short tower so climbing it really shouldn't be a concern.
Just buy the correct safety harness and "Y" 100% tie-off lanyard
(~$100 or so total) and get on with it with far less hassle than
trying to re-engineer the tower.

25'? try a tall ladder and a teenager.- Hide quoted text -

- Show quoted text -

To be honest, I dont like hights.

I wondered if I could make a steel base with three pieces of tube
bigger than the tube on the tower that would fit into the new tubes if
that makes sense. My tower is the three sided stuff and I think it is
steel but it may be aluminum. It is gray colored.

Also, it is hard to climb up it with a 10 foot long antenna in your
hand.


Climb the tower with a piece of rope attached at one end to your
climbing belt and the other end to theantenna (somewhere forward of
the CG. When you get to the top, secure yourself and pull the antenna
up to you. Do all the connecting work at the top. If you are
replacing an antenna, just drop the old one off, unless you are
planning on keeping it. In that case, use a piece of rope twice as
long as you need with the center attached to the belt. When on top,
attach the lose end to the old antenna and loosen it and lower it to
the ground then pull the new one up and install it. If the antenna is
very heavy (most TV antennae aren't) you can use a gin pole with a
pulley at the top to pull up the antenna and lower the old one. Sounds
like you may have Rohn 25 tower. I've been up and down those for
years. Just think SAFETY FIRST.

Jim

stryped wrote:
On Dec 20, 11:18 am, Jim Wilkins wrote:
On Dec 20, 11:13 am, stryped wrote:

I have an antenna tower in concrete behind my garage that has my
local tv station antenna. It is a big yagi type antenna. ...

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to
install the hinge. I appreciate any help.

It shouldn't be too hard but when you do it you need experienced
hands- on advice in person, not from the Internet. My 50 foot
antenna mast hinges down.

If the tower unbolts at the base you can hinge it there. Higher up
the hinge and lowest tower section will be pushed very hard sideways
when you lower the tower with a rope.

jsw

My tower is up againts the back of the garage with nothign else nearby
really. I do have an attic area above the garage. What i made a braket
out of angle iron with a pulley, atteched the braket to a couple of
studs through the attic wall. I have brick around my garage footer/
foundation. COuld I mound a hand crack winch directly into the brick/
block with concrete screws. Then run the winch rope/cable up through
the pulley and attaching the middle or top part of the mast. With a
hinge at the bottom of the tower, I could use the winch to raise lower
the mast? Just thinking out loud.

Sure thing - but I'd mount that winch to a backer board (2X12 ...) well
secured between studs instead of the brick . Then use two lengths of
pipe/tube to brace it upright . Spread 'em apart like a towbar to form a
triangle .

--
Snag
Learning keeps
you young !

This is a piece of cake. You have probably never heard of a mast tabernacle, but it has been in use for hundreds of years and
perhaps even longer. Please refer to http://pweb.netcom.com/~longyard/Mastraise.html

There you will find a more complete discussion.
Steve


"stryped" wrote in message ...
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

On Dec 20, 10:13*am, stryped wrote:
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

Here one idea for you:
http://www.dxzone.com/cgi-bin/dir/jump2.cgi?ID=12733
I'm sure you can find many more.

stryped wrote:

I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

I'd use a gin pole and take the thing down one more time in sections. Then I'd put the
hinge in. One of these days I have a Rohm 53' fold over I need to erect.

Wes
--
"Additionally as a security officer, I carry a gun to protect
government officials but my life isn't worth protecting at home
in their eyes." Dick Anthony Heller

Steve Lusardi wrote:
This is a piece of cake. You have probably never heard of a mast
tabernacle, but it has been in use for hundreds of years and perhaps
even longer. Please refer to
http://pweb.netcom.com/~longyard/Mastraise.html

There you will find a more complete discussion.
Steve


I like the idea of it, but my mast is over 30 feet long and weighs about
250 pounds!

--

Richard Lamb
email me:
web site: www.home.earthlink.net/~cavelamb

On Dec 20, 5:46*pm, "Steve Lusardi" wrote:
This is a piece of cake. You have probably never heard of a mast tabernacle, but it has been in use for hundreds of years and
perhaps even longer. *Please refer to

http://pweb.netcom.com/~longyard/Mastraise.html
Steve

Since you showed photos of good examples, my TV antenna is a variation
of a sliding Gunter rig:
http://en.wikipedia.org/wiki/Gunter

The fixed mast is attached to the house and extends about 4' above the
roof, with a guyed extension connected by a shiplap joint and bands.
The "gaff" upper section of antenna mast tubing has the rotator at the
bottom, attached to the track slide by a hinge, and the antenna at the
top. When I remove the upper extension and fully lower the gaff part I
can reach the antenna from the roof.

The halyard that raises it runs through upper and lower double sheave
pulleys, vertically in line for a lower profile, so the pull is small
enough to handle easily with cold bare hands in an icy night gale, ie
when I most need to lower the antenna.

The upper guy lines run over pulleys on a ring suspended (to permit
rotation) just below the antenna and down the mast to rope cleats.
This way I can tension them to straighten the antenna tubing, which
would be difficult from the outer ends of the guy lines.

For serious maintenance I can lower the slide to the ground and pivot
the antenna tube (gaff) down.

It's hard to describe without a drawing, and not clear from the photos
I've taken. I hope this is understandable.

jsw

"Wes" wrote in message
...
stryped wrote:

I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

I'd use a gin pole and take the thing down one more time in sections.
Then I'd put the
hinge in. One of these days I have a Rohm 53' fold over I need to erect.

Wes


I used to work on a crew of rig builders erecting and taking apart drilling
derricks. Typical was a Lee C. Moore 147. Today, it is all very much
heavier top driven units, and a floating gin pole is used. Yes, a gin pole,
and a guy on the ground with a cathead would make very short work of that
big a tower to bring it down. Then reassemble, make your hinge, put some
adjustable guy wires on it, lift it up, adjust the two guy wires, add a
third removable one, and be done with it. It would take longer to make the
gin pole than to take down the structure.

Steve

Just a thought - but one might
be able to take a leg, attach a hinge that will be over strong -
and do that on another leg - e.g. the two that fold under.

So if a 3 or a 4 pole mask - you need two with hinges.

Now put a locking hasp on the other one and lock it.

Set up a real heavy wire - or chain.

Probably want a car or truck to control the wire down/up.

Tricky at best.

Once you are sure you can handle it, you can cut the legs
at the center of the hinges and hasp(s).

Just a guess and a way - I suggest you get help
from a mechanical engineer and or a crane company.

Switching an antenna - gee whiz - call the local Motorola service man
and have the old one taken down and replaced with the new one.
One hire out and it is over.

Martin

On 12/20/2010 10:51 AM, Steve B wrote:
wrote in message
...
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

I have considered similar for raising owl boxes, and raptor perches. My
thoughts come down to three pad eyes, the center one being on the base of
the tower, the other two, set into a concrete base, all three match drilled
through, and secured by a heavy bolt. A pad eye is a D shaped piece of
metal, but can be long, with the hole drilled in the D. You've seen them as
lifting points on machinery. The one on the base of the tower would fit
between the two set in the concrete.

Lifting and lowering would have to be done with a winch or a vehicle, and a
three point guy system would make it steady.

Lowering the antenna in the first place for installation of the hinge part
would be the biggest process.

Raising would consist of leaving the two guy wires in place, and pulling on
the third, but using some sort of helping member to make the pulling cable
pull upward slightly rather than just horizontally. The two permanent guy
wires would hold the antenna safely in place while lowering and raising with
the third detachable one, once you have them to the correct length.

It would be some work at first, but then very easy to raise or lower it.
Align the hinge to bisect the line of the two stationary guy wires, and the
third perpendicular to that on the other side, all the same length. They
could be all the way to the top, or just 2/3 of the height, and be steady.

Take some pictures and share. Perhaps someone who has BTDT can give you
better advice, or another way if you post some pics.

Steve

On Dec 20, 9:02*pm, "Steve B" wrote:
...
...It would take longer to make the
gin pole than to take down the structure.

Steve

Do you know any good tricks for erecting a gin pole or shear legs
without a crane?

jsw

"Jim Wilkins" wrote in message
...
On Dec 20, 9:02 pm, "Steve B" wrote:
...
...It would take longer to make the
gin pole than to take down the structure.

Steve

Do you know any good tricks for erecting a gin pole or shear legs
without a crane?

jsw

I will try to explain it.

The gin poles we used in the oilfield were miniature jib cranes. They were
triangular in form, tapering from the base to the tip, where the single
pulley sheave was. There was no compound lifting sheaves, just a push/pull
that ran to a drawworks cathead capstan. As with anything, if all the
pressure is compression, and not sideloading, they will be incredibly
strong, and overkill.

The base of the gin poles we used was just a right angle of heavy flat bar
that rested on the bolts of the highest point of where bolts were used to
fasten two sections of outer legs together. A chain was used to hold the
base on the bolts, and the inward angle of the outer legs, plus a slight
cant in the base of the gin pole to the tip made it tip towards the inside
of the four sided hole at the top of the derrick, as does the jib section of
a common crane. When the element came loose, it was in the position to be
lowered through the middle of the square derrick. It is not, however,
adjustable, as a crane jib is, being held in place by the chain. In your
case with a triangular structure, you could make a bolt on heavy flat bar to
secure it on the mast. Or you might have to make slider hooks to lower it
onto the structural members of the lower section to rest on.

Several things are vital.

One is the safe working load of the rope. Ours was a custom made 1" four
strand manila with a reverse lay. Usable life was calculated like drilling
cable. Drilling cable was calculated in ton miles, that being how many tons
had been lifted, and how many miles of the cable had been run through the
sheaves. IOW, wear. Wear could be accurately determined either in this
rope, or 1 1/8" drilling cable by caliper measurement and visual wear
inspection. Rope was not calipered, and just common sense and visible wear
was the criterion. Any broken strands made it a boat anchor rope. We used
custom lengths of over 9,000' to change antennas on a 3,000' high KATV TV
antenna located south of Kaplan Louisiana were made and used. Remember, you
have to go up, and down, and have a 3,000 tagline to hold back the load. Up
and down was 6,000 feet to hook on to the antenna, then you had to pull it
back up and hold back on the remaining 3,000 feet because the weight of the
3,000 feet on the other side far outweighed the antenna, and once it got up
so high, it would take off on you, having more rope weight on one side, and
nothing holding it back on the other. Nearly two miles of rope was its own
bag of snakes. Draw cartoon diagrams to plan ahead for hold back tag lines
where needed.

Powering this was either a drilling drawworks, with maybe thousands of
horsepower on a drill rig, or if on a land rig and a light derrick, a
Continental fourbanger built on an I beam frame, running through a car
transmission, and out through a car rear end, but with brass capstan
catheads instead of car rims. This was always deadmanned to the ground, or
had 12" x 1" flatbar outriggers that pickup trucks would park on with their
tires on the flatbar. A cathead is a brass hourglass polished curved round
roller that allow for slippage, and the slippage can be controlled by
putting a specific number of turns on the cathead, and using hand pressure
on the loose end to pull it and make it grab, or loosening and making it
slip. Up/down. If you do not have access to a cathead, I have seen them
done off a truck rear wheel with a cathead attached. A very long capacity
electric winch could also be used, and with a 25 or 50' tower, not a real
lot of cable would be needed. By figuring your lengths, two cables could be
put together using thimbaled eyes and Crosby clamps, but they would have to
be calculated so they would not have to pass through a fairlead or onto a
winch drum.

Creating a lifting point directly over the section to be lifted is critical.
It is good to have the lifting line come up through the center of the
structure, but not absolutely a necessity. Having it straight up rather
than at an angle prevents side loading of the gin pole, that is, pulling on
it from the side rather than from right under it. You may have to rig a
snatch block at the bottom of the tower to fairlead the rope/cable through,
and change directions sending it up top. It may be able to do by parking
the cathead close to the base, just don't get it more than about ten feet
away from the base, as you will be pulling too far sideways, possibly
creating a catastrophic spectacular youtube failure.

Preparation is vital. You can loosen up the bolts and nuts on the section
you want to remove prior to removal, and this will tell you if they are
going to come off, will need some extra torque, are going to require an air
impact, or in worst case scenario, the need of a smoke wrench. (cutting
torch) But if you have your gin pole in place, secure, and lines taut, the
cutting of the bolts should not create a shock load on the section when it
does come loose. Watch the slag so it does not burn the rope. Avoid shock
loading at all costs, as momentary loads come into play, and can exceed SWL.

All this has to be a ballet. Slow and precise. No herky jerky. If you
have made your gin pole in a good design, it will support probably 5 times
what you are trying to lift. Buy quality steel, quality sheave, quality
chain, and quality welding. Use specific shackles to fasten the chain, and
NOT grab hooks. Build for weight and strength, but still try to make it as
light as you can, and it must be at least 60% of the length of the segment
to be removed/replaced. Tag lines and follow lines wrapped around the in
place segment can keep it from getting too far out of hand as it comes down
or goes up, just watch for hanging up on bolt heads or anything else. Cable
or chain can also be used. You want the slider cable/chain at the bottom of
the sliding section to keep it from flipping. Slow is the rule of the day.

Once you separate a section from the bolts, it will be hanging vertically
over your lower stack. Just push it aside, and let your cathead operator
lower it, scuffing along the tower, or attach a tag line, and have a ground
hand pull it away from the stack to prevent scuffing or hanging up. If you
want it to scuff along the in place sections, put your safety loop around
it. Do not use a vehicle, only manpower, as a vehicle can apply an
excessive amount of sideloading.

Now, your cathead and operator. It is a dirty oilfield heavy metal
operation that requires the touch of a surgeon. It takes ONE cathead
operator, and ONE person giving directions, so have a meeting ahead of time,
and assign a signal man, and instruct everyone else to either keep their
hands in their pockets or stuffed in their belt behind their backs, and
their mouths shut unless they see something clearly dangerous.

All gin poles must be manufactured with different things in mind. First,
the configuration of the element to be hoisted or lowered, which will
determine the configuration and shape of the "shoe" on which the pole will
rest. Second is the weight of the section that is going to be lifted or
lowered, wanting the gin pole to be at least 60% of the length of the
section.. Next is the length, although as long as you attach the lifting
line past center point vertically, you can use a shorter gin pole than the
section you are hoisting/lowering.

Gin pole configuration can consist of triangulated arrangement of pipes, and
then a continuous W shape of reinforcements, similar to what is used in bar
joists. Attachment of top pulley and bottom shoe is critical.

A consideration is weight, knowing that you will have to hoist this gin pole
in place to get to the highest section. In my latter days in derrick
erection, aluminum poles were coming into fashion, with aluminum welding
techniques being improved, and aluminum quality improving in the early 70's.
They were also much easier for a man or two to move from one leg to the
other, walking on top of the MicroLam scaffold boards.

The bottom section will not be able to be removed with a gin pole. You will
have to use tag lines, perhaps attached to trucks to lean it over. Removal
of the bottom bolts may be by wrenches, or a cutting torch.

Get yourself a good harness and tie off. Nuff said about that.

I know this is a lot, but in actuality, it is quite simple when eaten one
bite at a time. It is doable, but for someone doing it the first time, to
pull all of the components together is a bigger deal than a rig builder who
will have all this on one trailer. It really ain't rocket surgery, and we
have done some massive lifts just using 1" rope and a gin pole.

Trying to find some pics of a gin pole, but no luck so far. If you're
interested, I can draw one, and take a pic, and put it on flickr.

Rigbuilding, diving, working on boats, high climbing, working with
explosives, oil well drilling, ............. it was like getting to be a
pirate.

Steve

250lbs is not a problem. These things readily handle a ton+.
Steve

"CaveLamb" wrote in message ...
Steve Lusardi wrote:
This is a piece of cake. You have probably never heard of a mast
tabernacle, but it has been in use for hundreds of years and perhaps
even longer. Please refer to
http://pweb.netcom.com/~longyard/Mastraise.html

There you will find a more complete discussion.
Steve


I like the idea of it, but my mast is over 30 feet long and weighs about
250 pounds!

--

Richard Lamb
email me:
web site: www.home.earthlink.net/~cavelamb

If you were to look at a commercially-made pivoting base for typical light
duty triangle-type tower (essentially conduit and zigzagged steel rod)
you'll see that the anchoring points need to be very heavy duty.

Slight wind loads at the top of a 25 foot tower can generate a lot of stress
at the base.

A base I saw at a local dealer was made with parts fabricated from 1/2"
steel.. 2 "legs" pivot, and one separates with a heavy duty latching
mechanism.

You will most likely need to take the tower apart/down (top first) to
install a proper pivoting base.

If the tower were oriented properly (one triangle point toward the wall), a
winch could be installed in the garage for lowering the tower away from the
wall.

You might be further ahead to rent or hire a bucket truck for an hour to
allow you to get up there to change the antenna more easily, and be done
with it.

--
WB
..........


"stryped" wrote in message
...
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

On Dec 21, 1:44*am, "Steve B" wrote:
"Jim Wilkins" wrote in message
...
Do you know any good tricks for erecting a gin pole or shear legs
without a crane?
jsw

I will try to explain it.

The gin poles we used in the oilfield were miniature jib cranes. *They were
triangular in form, tapering from the base to the tip, where the single
pulley sheave was. *...
Steve

Thanks for taking the time and effort to type all that, which I saved.
I've helped other hams work on radio antennas, and learned the Army's
version of field rigging.

jsw

"Jim Wilkins" wrote in message
...
On Dec 21, 1:44 am, "Steve B" wrote:
"Jim Wilkins" wrote in message
...
Do you know any good tricks for erecting a gin pole or shear legs
without a crane?
jsw

I will try to explain it.

The gin poles we used in the oilfield were miniature jib cranes. They were
triangular in form, tapering from the base to the tip, where the single
pulley sheave was. ...
Steve

Thanks for taking the time and effort to type all that, which I saved.
I've helped other hams work on radio antennas, and learned the Army's
version of field rigging.

jsw

If you can get some pictures, that would explain it all. If you have a lot
of buds, it may be cost feasible to make one, and have it on hand for all.
For the loads you are lifting, you wouldn't have to make an incredibly big
or strong one, and you could use a winch with a good capacity of cable, or
just tag onto the end of the cable with what you occasionally use for
hoisting. The main thing is getting some good harnesses and using them
right. I just saw a thing this morning where Spiderman went splat on
Broadway, his cable snapping, So, even when you know how to do it right,
you can still get a boo boo.

Steve

On Dec 21, 11:33*am, "Steve B" wrote:
...
Thanks ...
jsw

If you can get some pictures, that would explain it all. *If you have a lot
of buds, it may be cost feasible to make one, and have it on hand for all..
For the loads you are lifting, you wouldn't have to make an incredibly big
or strong one, and you could use a winch with a good capacity of cable, or
just tag onto the end of the cable with what you occasionally use for
hoisting. *The main thing is getting some good harnesses and using them
right. *I just saw a thing this morning where Spiderman went splat on
Broadway, his cable snapping, *So, even when you know how to do it right,
you can still get a boo boo.

Steve

I have a set of shear legs and a shop crane with off-pavement wheels
that will lift a ton or two as high as I need. I really want to learn
more so I know better what jobs to take or avoid, for myself or as
favors for friends.

jsw

In rec.crafts.metalworking on 2010-12-21 Steve B wrote:
"Jim Wilkins" wrote ...
On Dec 20, 9:02 pm, "Steve B" wrote:
...It would take longer to make the
gin pole than to take down the structure.

Do you know any good tricks for erecting a gin pole or shear legs
without a crane?
[snip lots of good stuff]

One is the safe working load of the rope. Ours was a custom made 1" four
strand manila with a reverse lay. Usable life was calculated like drilling
cable. Drilling cable was calculated in ton miles, that being how many tons
had been lifted, and how many miles of the cable had been run through the
sheaves. IOW, wear. Wear could be accurately determined either in this
rope, or 1 1/8" drilling cable by caliper measurement and visual wear
inspection. Rope was not calipered, and just common sense and visible wear
was the criterion. Any broken strands made it a boat anchor rope. We used
custom lengths of over 9,000' to change antennas on a 3,000' high KATV TV
antenna located south of Kaplan Louisiana were made and used. Remember, you
have to go up, and down, and have a 3,000 tagline to hold back the load.
....

All those 3000' refs should be 2033' per fox16.com link below, or
2000', per at http://en.wikipedia.org/wiki/KATV_tower. The tallest
transmission tower in the world (2063') is 38 miles north of Fargo,
ND. It was built in 1963, a couple of years before the KATV tower.
http://en.wikipedia.org/wiki/KVLY-TV_mast says FCC and FAA have
since made it difficult to get permits for structures over 2000' feet
above ground level.

Now, your cathead and operator. It is a dirty oilfield heavy metal
operation that requires the touch of a surgeon. It takes ONE cathead
operator, and ONE person giving directions, so have a meeting ahead of time,
and assign a signal man, and instruct everyone else to either keep their
hands in their pockets or stuffed in their belt behind their backs, and
their mouths shut unless they see something clearly dangerous.
...

For example, " 'Apparently the top of the temporary jack cable we had
up top pulled out of the clamps at the anchor and let the top (of the
tower) bend over. That's what started the whole thing,' says President
of Structual Systems Technology Fred Purdy." -- from
http://www.fox16.com/news/local/story/2-000-Foot-Television-Tower-Collapses-One-Person/68WK3qaluUCutn6STJP2GA.cspx

Rigbuilding, diving, working on boats, high climbing, working with
explosives, oil well drilling, ............. it was like getting to
be a pirate.



--
jiw

Steve B wrote:

"Jim Wilkins" wrote in message
...
On Dec 21, 1:44 am, "Steve B" wrote:
"Jim Wilkins" wrote in message
...
Do you know any good tricks for erecting a gin pole or shear legs
without a crane?
jsw

I will try to explain it.

The gin poles we used in the oilfield were miniature jib cranes. They were
triangular in form, tapering from the base to the tip, where the single
pulley sheave was. ...
Steve

Thanks for taking the time and effort to type all that, which I saved.
I've helped other hams work on radio antennas, and learned the Army's
version of field rigging.

jsw

If you can get some pictures, that would explain it all. If you have a lot
of buds, it may be cost feasible to make one, and have it on hand for all.
For the loads you are lifting, you wouldn't have to make an incredibly big
or strong one, and you could use a winch with a good capacity of cable, or
just tag onto the end of the cable with what you occasionally use for
hoisting. The main thing is getting some good harnesses and using them
right. I just saw a thing this morning where Spiderman went splat on
Broadway, his cable snapping, So, even when you know how to do it right,
you can still get a boo boo.

Steve

Good full body harness, "Y" 100% tie-off shock absorbing lanyard to the
back "D" ring, and an extra plain lanyard for positioning via the hip
"D" rings. Not especially expensive these days either, and certainly
less than your insurance deductible.

stryped wrote:
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

I think the suggestion of hiring an antenna guy or a bucket truck were
good ones, but if you have to swap out the antenna yourself, another
option would be to rent scaffolding and that way you can work from a
stable platform. Antenna's seldom need service so the rental expense
would be a one or two time event, a whole lot cheaper than cable or
dish TV.

Roger Shoaf

On Mon, 20 Dec 2010 10:59:41 -0800 (PST), stryped
wrote:

On Dec 20, 11:18*am, Jim Wilkins wrote:
On Dec 20, 11:13*am, stryped wrote:

I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. ...

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

It shouldn't be too hard but when you do it you need experienced hands-
on advice in person, not from the Internet. My 50 foot antenna mast
hinges down.

If the tower unbolts at the base you can hinge it there. Higher up the
hinge and lowest tower section will be pushed very hard sideways when
you lower the tower with a rope.

jsw

My tower is up againts the back of the garage with nothign else nearby
really. I do have an attic area above the garage. What i made a braket
out of angle iron with a pulley, atteched the braket to a couple of
studs through the attic wall. I have brick around my garage footer/
foundation. COuld I mound a hand crack winch directly into the brick/
block with concrete screws. Then run the winch rope/cable up through
the pulley and attaching the middle or top part of the mast. With a
hinge at the bottom of the tower, I could use the winch to raise lower
the mast? Just thinking out loud.


Up against a building ? Never mind. I'd put the hinges on first and
then cut those two ... Look at off grid wind power designs.


SW

"Jim Wilkins" wrote in message
...
On Dec 21, 11:33 am, "Steve B" wrote:
...
Thanks ...
jsw

If you can get some pictures, that would explain it all. If you have a lot
of buds, it may be cost feasible to make one, and have it on hand for all.
For the loads you are lifting, you wouldn't have to make an incredibly big
or strong one, and you could use a winch with a good capacity of cable, or
just tag onto the end of the cable with what you occasionally use for
hoisting. The main thing is getting some good harnesses and using them
right. I just saw a thing this morning where Spiderman went splat on
Broadway, his cable snapping, So, even when you know how to do it right,
you can still get a boo boo.

Steve

I have a set of shear legs and a shop crane with off-pavement wheels
that will lift a ton or two as high as I need. I really want to learn
more so I know better what jobs to take or avoid, for myself or as
favors for friends.

jsw

For the size towers you are talking about, you will find that in comparison
to the equipment, knowledge, and experience you already have in your work
pool, this will be TinkerToys. But the first experiences will be learning
ones, and never having done it before, you will have a bit of a learning
curve. Maybe you could advertise for an experienced hand, maybe get an old
oilfield derrick erector, or tower erector, and have him/her/it give you a
jump start. You might even pick up a gin pole cheap and save yourself that
part of the equation. Advertise on craigslist, it's free. Try in Houston,
Lafayette LA, and other oil centers. You never know.

Steve

On Dec 21, 2:13*am, stryped wrote:
I have an antenna tower in concrete behind my garage that has my local
tv station antenna. It is a big yagi type antenna. It has been there,
both the antenna and tower, for 12 years. I am getting a little older
and dont have any help and to be honest, dont like climbing up it. I
think the tower is 25 feet ot so from it's top to the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to install
the hinge. I appreciate any help.

OK, I can tell you how to do it. You need a bit of clearance round the
mast, least a foot, preferably more. I've done it, still standing.
(And stuff all this "Weldor " crap going on here - the ONLY commercial
weld in the whole structure I built - bout 7m tall - broke - migged,
looked good, but **** all penetration.) I rebuilt it meself with my
little DC inverter welder. And thinking a bit about a decent design.
Spacers between the 2 plates, enabled decent weld to hinge structure.
Used ordinary 25c washers, tack welded them in. so much for
"Professional Weldor"

Basically, you need a gin pole stood next to the mast, high as
possible, preferably half the height. Needs to be dug in and
concreted, its your lowering point via a winch. Bout 50mm sq, 2mm or
better would be cool.

You want more, let me know. Not an engineer, just someone who builds
things.

Andrew VK3BFA.

In article
,
stryped wrote:

On Dec 20, 11:11*am, "chaniarts" wrote:
Pete C. wrote:
Steve B wrote:

"stryped" wrote in message
...
I have an antenna tower in concrete behind my garage that has my
local tv station antenna. It is a big yagi type antenna. It has
been there, both the antenna and tower, for 12 years. I am getting
a little older and dont have any help and to be honest, dont like
climbing up it. I think the tower is 25 feet ot so from it's top to
the ground.

Would it be possible to make a hinge for this thing so I could bring
it down to replace the anteena? Can I do it now that it is already
errected, maybe loosening at one of the sections and pulling it off,
installing the made hinge then putting back on? Would I be able to
lift the tower and antenna by myself once it is pulled off to
install the hinge. I appreciate any help.

I have considered similar for raising owl boxes, and raptor perches.
My thoughts come down to three pad eyes, the center one being on the
base of the tower, the other two, set into a concrete base, all
three match drilled through, and secured by a heavy bolt. *A pad eye
is a D shaped piece of metal, but can be long, with the hole drilled
in the D. *You've seen them as lifting points on machinery. *The one
on the base of the tower would fit between the two set in the
concrete.

Lifting and lowering would have to be done with a winch or a
vehicle, and a three point guy system would make it steady.

Lowering the antenna in the first place for installation of the
hinge part would be the biggest process.

Raising would consist of leaving the two guy wires in place, and
pulling on the third, but using some sort of helping member to make
the pulling cable pull upward slightly rather than just
horizontally. *The two permanent guy wires would hold the antenna
safely in place while lowering and raising with the third detachable
one, once you have them to the correct length.

It would be some work at first, but then very easy to raise or lower
it. Align the hinge to bisect the line of the two stationary guy
wires, and the third perpendicular to that on the other side, all
the same length. *They could be all the way to the top, or just 2/3
of the height, and be steady.

Take some pictures and share. *Perhaps someone who has BTDT can give
you better advice, or another way if you post some pics.

Steve

There are a lot of ways to do it and a lot of types of towers that
dictate the correct way to do it for that tower. Honestly, 25' is an
extremely short tower so climbing it really shouldn't be a concern.
Just buy the correct safety harness and "Y" 100% tie-off lanyard
(~$100 or so total) and get on with it with far less hassle than
trying to re-engineer the tower.

25'? try a tall ladder and a teenager.- Hide quoted text -

- Show quoted text -

To be honest, I dont like hights.

I wondered if I could make a steel base with three pieces of tube
bigger than the tube on the tower that would fit into the new tubes if
that makes sense. My tower is the three sided stuff and I think it is
steel but it may be aluminum. It is gray colored.

Also, it is hard to climb up it with a 10 foot long antenna in your
hand.

You missed the point. Teenagers are fearless and immortal. Hire one for
a day. The experience will likely change his (or, if you're lucky, her)
life, but there is an unending supply of teenagers.

-Frank

--
Here's some of my work:
http://www.franksknives.com

On Wed, 22 Dec 2010 18:29:48 -0800, Frank J Warner
wrote:

Here's some of my work:
http://www.franksknives.com

Domain offline, Frank!

Unfortunately, I have visited your site before and can't afford one of
your _nice_ knives. What do you think of the Cold Steel Kobun tanto?

(Apologies for posting a metalworking-related question here on RCM)

--
Remember, in an emergency, dial 1911.