My winch is mounted to the tower, but the operator doesn't stand directly
under the load. The foot switch has a 10-foot cord. I could have made it
longer, but when raising sections we felt the winch operator was a safe
distance away from the load, should it have fallen. However, this is not the
case when an antenna is being trammed, which is what we were talking about.
I don't think my ground man figured out that he could move the section in
tiny increments by letting the rope slip. He just tapped on the foot switch.
He was able to control the raise/drop within about a half inch that way,
sufficient for me to get the legs aligned. The only trouble we had was with
three sections where the legs didn't quite align (yes, we should have
measured on the ground...) Two of the sections had to go back down for
gentle persuasion with a sledge. I was able to give the third one a
well-placed tap with my hand sledge while on the tower to get it to slip on.
I think that was the only section where the fit was tight enough that I had
to use the Tower Jack.
I used a heavy-duty 12-foot gin pole from WB0W. It's designed for use on
larger towers like Rohn 55. As long as the clamp is placed as high on the
leg as possible, and the haul rope is attached about 3/4 of the way up the
section to be lifted, there's plenty of clearance for 10-foot sections. The
1/4"-wall aluminum pole never even came close to bending under any of the
weight we applied.
The WB0W gin pole is excellent, very well-designed and very well-built. The
clamp is adjustable for a wide range of tower leg sizes. My one complaint is
that it's *really* heavy. Probably the most challenging part of stacking my
tower was moving the gin pole up for the next section. I tried a couple of
different methods: 1) lowering the head, tying it off, and using the rope to
haul the retracted pole up to the top of the next section (very difficult
due to the weight of the pole); and 2) clipping the head to the top of the
section just installed, climbing down, fixing a safety line to the clamp,
and sliding the clamp up the pole (easy, but time-and-energy consuming.)
Several times I considered rigging a separate pulley to haul the pole, but
never got around to it. Of course, I did so when it came time to lower the
pole to the ground.
73, Dick WC1M
> -----Original Message-----
> From: Thomas Tow [mailto:ttow1@charter.net]
> Sent: Tuesday, December 19, 2006 11:50 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] Capstan
>
> Under the tower scares the bejeebies out of me. We erected my
> 110' Rohn 55 easily using a heavy rope and capstan winch. The
> winch was mounted on a trailer hitch type of apparatus on the
> installers flatbed truck..approx 75'
> away from the tower. We used two Rohn 25 sections with top
> mounted pulleys as a gin pole and they were chained to each
> installed Rohn 55 section as we went up. We even lifted
> sections with a tic ring mounted, side mounts, guy brackets
> etc. Easily done. I used a foot switch at the winch and then
> using my hand tension on the capstan rope itself to move in
> tiny..maybe1/8 inch up or down movements as needed while he
> matched the sections and set the bolts.
> Incredible to be able to be that far away and move those
> sections so slightly to help align the bolt holes..pretty
> cool...and from a safe distance. I will never do it any other
> way on heavy sections...maybe using a gin pole on Rohn 25
> would be easier.. but anything directly under the tower is
> asking for disaster whatever the load. A falling tower
> section or most anything else 100' up has no respect for a
> hardhat Tommy WD4K
>
>
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