My advice, based upon raising 5 Universal towers of 60+ feet using the
'falling derrick' method:
1. Put the derrick AT the tower base and attach to the tower at or
above the 30' mark. (I use a 40' attachment)
2. When the tower is sufficiently raised to the point where the
rope/cable lifts from the derrick, stop and remove the derrick.
3. Continue pulling the tower to the raised position and stop JUST
BEFORE vertical alignment.
4. There will be tension on the lifting rope/cable sufficient to hold
the tower while you insert the missing base bolts at this time.
5. After inserting ALL the remaining base bolts, detach the
rope/cable from the tower. (At this point, you may have to climb to
the attchment point. I do NOT as I use sufficient rope to make a loop
from the pulling vehicle to the tower and BACK.
Good luck
Don
N8DE
Quoting John Kemker <john@kemker.org>:
> On a similar note, anyone have any suggestions on an appropriate hoist
> to use for lifting a Universal 60 ft. tower into place? I'm planning on
> putting a "derrick" up made out of a couple of sections of Rohn 25G to
> assist in raising and lowering the tower. Universal states the tower
> weighs 256 lbs. and one of their engineers suggests attaching to the
> tower to be raised at 20 ft. While an electric hoist isn't necessary,
> it'd be nice, as long as it isn't too expensive. The derrick will be
> approximately 20 ft. away from the tower and the hoist will be mounted
> at the base of the derrick, with a pully at the top of the derrick.
> General idea is to leave the hoisting cable attached to the tower at all
> times, but not holding tension when the tower is fully raised. Other
> option is to split the raising cable between the tower and the derrick
> with a heavy-duty link and detach when fully raised and let the tower
> length hang down out of the way.
>
> --JohnK
> 73 de W5NNH
> 10X 75371/M&M 117/SMIRK 6185/Six Club 285/TRA 2499/Norcross 228 F&AM
>
>
>
> F.R. Ashley wrote:
>> Hi all,
>>
>> Great advice here. A year or so ago I checked into a replacement wince for
>> my old Tow-Tec on my Hygain HG55 crank up tower. I quickly found out there
>> is a great difference between a WINCH and a HOIST. Most winches are NOT
>> designed to hold anything up, at least for long. Winches PULL, hoists
>> LIFT (and hold). I would not trust any of the winches designed for
>> mounting on the front of a jeep, etc.. they are for PULLING only!
>> Also, make dang sure your winch or hoist will not FREE SPOOL! That is a
>> disaster in the making. I'd also carefully check its braking capability and
>> limits.
>> I also checked with US Towers and they say theirs are not winches or hoists,
>> but "electric motor drives".
>>
>>
>> 73 Buddy WB4M
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