Rohn 45
 

I'm in need of a Rohn BPL45G to convert a standard 10 foot section of Rohn
45 to a flat top for installing a thrust bearing.
If anyone has one in good conditon or a new on laying around pleae let
me know what you would be asking for it.
73 Bill W4OM

On Sun, 19 Oct 2003 21:19:48 GMT, Bill wrote:

I'm in need of a Rohn BPL45G to convert a standard 10 foot section of Rohn
45 to a flat top for installing a thrust bearing.
If anyone has one in good conditon or a new on laying around pleae let
me know what you would be asking for it.
73 Bill W4OM

If you have a standard top section, or just a straight section, just
get one of the heavy duty rotor plates and mount the thrust bearing on
that.

I do have one of the top sections with top plate and thrust bearing,
but I also use the heavy rotor plate for another thrust bearing down
in the tower.

Using a standard 10 foot section I'd use two rotor plates (both with
thrust bearings. One just below the first cross braces at the top and
the second about 4 feet down. The find something to cap the tower
legs.

On mine with the top plate, I use one thrust bearing there and another
just above the rotor about 25 feet down inside the tower.

It's easy enough to weld up (and bend) a top plate, but not so easy to
get it double hot dipped galvanized. That is one heavy piece of
steel. I think it's either 5/16ths or 3/8ths inch plate.
If you don't weld you could take the diagram of the top plate to a
metal shop, get it cut and drilled and have three legs welded on that
will just fit over the top of the tower legs. Then bolt together in
the usual fashion. Remembering that ROHN uses 2 bolts per leg with
one being 5/16ths and the other is either 3/8ths or 7/16ths. If I had
my catalog handy I'd look it up, but I don't know where I put the
thing.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)

Yes it is one heavy piece of steel. Since my tower is a fold over
I dispensed with the Rohn version and obtained an aluminum plate
to which I fastened three rods using a bolt thru the plate aproach.
These three rods push fit into the Rohn tower legs.
Once in place they stay there thus no water build up
in the tower legs. It sure escapes me why Rohn made the top
plate so heavy especialy when they limit the top loading for
fold over use.
Perhaps they were concerned that the tower would split
down the middle instead of buckling when guys were over tightened.
Grin
Art



Roger Halstead wrote in message . ..
On Sun, 19 Oct 2003 21:19:48 GMT, Bill wrote:

I'm in need of a Rohn BPL45G to convert a standard 10 foot section of Rohn
45 to a flat top for installing a thrust bearing.
If anyone has one in good conditon or a new on laying around pleae let
me know what you would be asking for it.
73 Bill W4OM

If you have a standard top section, or just a straight section, just
get one of the heavy duty rotor plates and mount the thrust bearing on
that.

I do have one of the top sections with top plate and thrust bearing,
but I also use the heavy rotor plate for another thrust bearing down
in the tower.

Using a standard 10 foot section I'd use two rotor plates (both with
thrust bearings. One just below the first cross braces at the top and
the second about 4 feet down. The find something to cap the tower
legs.

On mine with the top plate, I use one thrust bearing there and another
just above the rotor about 25 feet down inside the tower.

It's easy enough to weld up (and bend) a top plate, but not so easy to
get it double hot dipped galvanized. That is one heavy piece of
steel. I think it's either 5/16ths or 3/8ths inch plate.
If you don't weld you could take the diagram of the top plate to a
metal shop, get it cut and drilled and have three legs welded on that
will just fit over the top of the tower legs. Then bolt together in
the usual fashion. Remembering that ROHN uses 2 bolts per leg with
one being 5/16ths and the other is either 3/8ths or 7/16ths. If I had
my catalog handy I'd look it up, but I don't know where I put the
thing.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)

On 22 Oct 2003 17:29:12 -0700, (Art Unwin KB9MZ)
wrote:

Yes it is one heavy piece of steel. Since my tower is a fold over

The tower section with the top plate is 7 feet long instead of 10, yet
it weighs the same. That means the top plate weighs the same as 3 feet
of tower, or 30#. The standard 45 G is 90# per section.

I like the aluminum plate idea. On mine I'd have to use 3/8ths or 1/2
inch but it'd be one whale of a lot lighter than the steel plate.

Mine has the heavy side and bending load, hence I really do need a lot
of strength up there.

I dispensed with the Rohn version and obtained an aluminum plate
to which I fastened three rods using a bolt thru the plate aproach.
These three rods push fit into the Rohn tower legs.
Once in place they stay there thus no water build up
in the tower legs. It sure escapes me why Rohn made the top
plate so heavy especialy when they limit the top loading for
fold over use.
Perhaps they were concerned that the tower would split

Which would happen first? break the tower apart or pull the guy
anchors out of the ground? Mine weigh 17,000# each. I guess the tower
would fail first, but I'll bet the anchors would no longer be level.

:-))

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)
down the middle instead of buckling when guys were over tightened.
Grin

I may have to go and use one of the rotor plates for that function, I do
have access to a machine shop where I could have one fabricated but I
was looking for an original if I could find one.
Thanks.
Bill

Roger Halstead wrote:
On Sun, 19 Oct 2003 21:19:48 GMT, Bill wrote:


I'm in need of a Rohn BPL45G to convert a standard 10 foot section of Rohn
45 to a flat top for installing a thrust bearing.
If anyone has one in good conditon or a new on laying around pleae let
me know what you would be asking for it.
73 Bill W4OM


If you have a standard top section, or just a straight section, just
get one of the heavy duty rotor plates and mount the thrust bearing on
that.

I do have one of the top sections with top plate and thrust bearing,
but I also use the heavy rotor plate for another thrust bearing down
in the tower.

Using a standard 10 foot section I'd use two rotor plates (both with
thrust bearings. One just below the first cross braces at the top and
the second about 4 feet down. The find something to cap the tower
legs.

On mine with the top plate, I use one thrust bearing there and another
just above the rotor about 25 feet down inside the tower.

It's easy enough to weld up (and bend) a top plate, but not so easy to
get it double hot dipped galvanized. That is one heavy piece of
steel. I think it's either 5/16ths or 3/8ths inch plate.
If you don't weld you could take the diagram of the top plate to a
metal shop, get it cut and drilled and have three legs welded on that
will just fit over the top of the tower legs. Then bolt together in
the usual fashion. Remembering that ROHN uses 2 bolts per leg with
one being 5/16ths and the other is either 3/8ths or 7/16ths. If I had
my catalog handy I'd look it up, but I don't know where I put the
thing.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)

On Sat, 25 Oct 2003 22:40:35 GMT, Bill wrote:

I may have to go and use one of the rotor plates for that function, I do
have access to a machine shop where I could have one fabricated but I
was looking for an original if I could find one.

Good luck on finding one. There should be some dealers who still have
some parts left.

If I had much wind load I'd certainly want to use the standard top
plate or have the equivalent made as it's at least 4 times as heavy
and wayyyy stronger than the rotor plate.

Roger Halstead (K8RI EN73 & ARRL Life Member)
www.rogerhalstead.com
N833R World's oldest Debonair? (S# CD-2)