When space is at a premium and you don't have to move the load too far, a
turnbuckle is the answer.
73 Don
VE6JY
On Mon, Apr 25, 2016 at 3:05 AM, Grant Saviers <grants2@pacbell.net> wrote:
> Les,
>
> IMO, the best idea is to attach a u-bolt with a hoist point bracket to the
> mast and use a come-along inside to the tower top plate, although
> come-alongs can be too long to fit. The shortest headroom lifters I've
> found is are 500# and 1000# capacity lever chain hoists, < 8". This is my
> strategy for a safe very heavy mast lift off the rotator, even if a foot or
> more of clearance is needed. A forged eye is fitted to a hole drilled in
> the top plate of the tower as an attachment point. Once installed, the
> attach points can be left for the "next time".
>
> Other ways to go: the die pry bar set from Harbor Freight and the 4 ton
> hydraulic frame straightener have been very handy for me to
> lift/separate/straighten things.
>
> #68339 or #1654 (the porta power from HF is now 2x the price from
> Amazon)
>
>
> http://www.amazon.com/Goplus%C2%AE-Porta-Power-Hydraulic-Repair/dp/B017H8R9E2/ref=sr_1_1?ie=UTF8&qid=1461551404&sr=8-1&keywords=hydraulic+frame+repair+kit
>
> the jaw separator might be useful for lifting once a pry bar gives some
> space for it, but needs a good purchase. Or use the small extension
> cylinder to a u-bolt fastened lift point above the tower top. Or use a
> small scissor jack, which I bought for taking apart rohn 25. The cylinders
> are also good for straightening bent tower parts.
>
> On a used 2800 I acquired the prior owner had secured a cut off box end
> wrench on the center bolt with a screw through the wrench handle and
> threaded into the Orion plate about 2" out from the bolt, oriented so the
> split mast clamp clears the wrench. Now I know why he did that.
>
> Grant KZ1W
>
>
> On 4/24/2016 19:11 PM, Les Kalmus wrote:
>
>> I came home from Visalia to find my antenna system freewheeling. The mast
>> holds 4 yagis, one of which is very large, and is rotated by an Orion
>> rotator.
>> If my suspicions are correct, the problem is the little 1/4" bolt holding
>> the shaft up into the bottom of the mast clamp has loosened and allowed the
>> shaft to fall.
>>
>> The tower is lowered and the antennas are tied off to a tree. I have
>> removed the mast clamp and now I have to raise the mast about 1/2" to free
>> the centering block so I can remove it to inspect that bolt.
>> I have a come along with an additional block with which I can lift the
>> mast, but the carabiner I have won't fit into the small space between the
>> centering block and the inside of the mast.
>>
>> Any suggestions on a way to either hook the mast from the bottom or to
>> clamp to it so I can raise it? We're talking maybe 400 lbs in the complete
>> antenna system.
>> I have done this in the past but I think I didn't have the centering
>> block at that time so it was easier to get something hooked into the bottom
>> of the shaft.
>>
>> Les W2LK
>>
>>
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>>
>>
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