Wasn't quite planning on a "falling derrick" style operation. More of a
fixed derrick operation.
--JohnK
73 de W5NNH
10X 75371/M&M 117/SMIRK 6185/Six Club 285/TRA 2499/Norcross 228 F&AM
n8de@thepoint.net wrote:
> 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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>
>
>
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