In a message dated 8/21/02 2:41:59 PM Pacific Daylight Time, n0rq@swbell.net
writes:
> It will be assembled on the ground and raised by a crane. How does one
> attach a Rohn 25 ginpole to the top for the purpose of hauling the HF beam (
> Force 12 XR-5) to the top? Is there some better way to get it up there?
First, the Rohn 25/45 ginpole WILL NOT fit on anything but Rohn 25/45.
You can adapt the mast but the leg fixture will be useless.
Why not use the crane to lift everything up while he's there? Have him
stand the tower, then have him pick up the mast and then the antennas.
Couldn't be easier.
>
> Also, how much stuff can I attach to the tower before the crane arrives? (
> The theory being it is easier to do it on the ground than in the air.) I
> plan to have the rotor and coax switch mounted, along with the associated
> cables (tied up inside the tower),
Another LXC Law states that you should "Break everything down into the
simplest task". Trying to do 2 or more things at once (i.e. pull up something
with cables attached) almost always results in problems. Break everything
down into bite-sized chunks. Put up the tower and then bring up the cables
later. This can be done without the help of the crane so don't worry about it
while the crane is there. (Exception - you need jumpers from the antennas to
the mast so that you can connect the feedlines coming up the tower.)
> but can I also have mounted:
> * the mast (9' of which is above the thrust bearing)?
> * the 6m beam (M2 12' boom) at the top of the mast?
> * the side brackets for the side-mounted 2m vertical?
> * the 3' PVC stubs that will hold the pulleys for the dipoles?
See advice above. Option one - Have the crane bring a manbasket. After he
drops the mast into the tower while you're standing there guiding it in, get
in the manbasket and carry up the 6m antenna and attach it to the top of the
mast. Same with the other mast stuff. (It's better to start at the bottom of
the mast for antenna placment/installation but you didn't mention anything
else of significance on the mast.)
Option 2 - have the mast ready to go with your antennas and appurtenances
and have the crane operator drop the whole thing in the tower. Then it's just
a matter of hooking up the cables from the tower.
> How much risk is there in installing those before it is lifted up?
They'll interfere with the crane haul cable. Break everything down to
single tasks.
>
> Any suggestions for the crane operator -- how far up to attach the crane,
> what to use or not use as a strap around the legs, do or don'ts for
lifting,
> etc.
>
The best thing is to have enough headroom above the tower so that the
tower hangs straight so you can drop it right on the base attachment pieces.
(HINT: Get one of those ratchet tie-downs from your hardware store and put it
around the bottom of the bottom section to pull the legs together - it'll
make mating the sections much easier.)
The operator is a professional, has done this before and has slings with
him that you can use. The problem is that his slings are for really BIG lifts
so they're not real handy for smaller ham-type stuff. Shouldn't be be a big
problem.
If everything is ready to go when he arrives, he should be gone in an
hour or two. Good luck!
Cheers,
Steve K7LXC
TOWER TECH -
Professional tower services for commercial and amateur
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