[TowerTalk] Legs of a 60' piece of tower being dragged while being lifted

[Grant Saviers]

I sent Steve K8LX a photo and he now understands the problem. Unless you 
have a ring at the bottom end of a section what you are doing should be 
fine.

Grant KZ1W

On 10/18/2016 4:29 AM, StellarCAT wrote:
> Hi Grant,
>
> Indeed it was about one ring - and that ring is near the top (48' 
> level of a 60' stick) ...and determining the COG isn't that difficult 
> at all using sum of moments. It should be pretty straight forward. 
> Assuming he booms out as he lifts to keep it on a radius, which is the 
> key, there will always be a force at the end pushing it down in to the 
> ground so again assuming he booms out as he lifts on a radius it 
> should stay planted. Not that difficult I'd guess for an experienced 
> operator. I've seen them place something within an inch of where you 
> need it at a distance of 100' from where they sit ... that stated I 
> will try to get something under the legs as it will more than likely 
> get dragged at least a little.
>
> Gary
> K9RX
>
>
> -----Original Message----- From: Grant Saviers
> Sent: Monday, October 17, 2016 10:39 PM
> To: Steve Maki ; towertalk
> Subject: Re: [TowerTalk] Legs of a 60' piece of tower being dragged 
> while being lifted
>
> Since my largest tower went up with a commercial tower company who
> builds 400' plus towers, and who required the base be managed, I would
> say there are definite disagreements about this.   When lifting sections
> with rings off supports, it can't be done safely and reliably, no matter
> the skill of the crane op.  A plain stick of Rohn 25/45/55 is a
> different animal.  Note the thread origin is about tower sections with
> rings already mounted.
>
> Grant KZ1W
>
> On 10/17/2016 18:55 PM, Steve Maki wrote:
>> On 10/17/2016 11:53 AM, john at kk9a.com wrote:
>>
>>> The weight is irrelevant.  A skilled crane operator can move the 
>>> boom as
>>> it is being lifted leaving the section on the ground as a pivot point.
>>> Of  course if someone wishes to build a slide or use a loader to move
>>> the base as it is being lifted that is perfectly fine, but I won't be
>>> doing this.
>>>
>>> John KK9A
>>
>> I agree. A good operator has no problem at all with this scenario, as 
>> long as the crane is sized properly and can be positioned properly.
>>
>> It's just a non-issue.
>>
>> -Steve K8LX
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