What is the best location on a 60' hinged tower to attach a line for lifting?

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    Lifting Tower
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Discussion Overview

The discussion revolves around determining the optimal location on a 60' hinged antenna tower for attaching a line to facilitate lifting the tower. Participants explore various factors affecting the lifting process, including mechanical considerations, safety, and the use of equipment such as pulleys and rope pullers.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • The original poster questions whether a specific formula for calculating tension will hold if the attachment point is moved up the tower.
  • Participants inquire about the mechanics of the lifting process, including whether the line will be held by hand or if there is room to maneuver while pulling the tower.
  • One participant suggests that a mathematical analysis would require diagrams or detailed descriptions of the setup.
  • Concerns are raised about the stability of the hinge against side-to-side movement, with a recommendation for multiple lines to ensure control during the lifting process.
  • Another participant asks about the height of the pulley connection points to better understand the lifting dynamics.
  • The original poster mentions the use of a 3/4 ton rope puller and a 1/2" rope rated for 6,500 lbs, along with plans to use pulleys for guiding the rope.
  • There is a suggestion to experiment with different attachment schemes while being cautious of potential damage.

Areas of Agreement / Disagreement

Participants express various concerns and suggestions, but there is no consensus on the best approach or specific attachment point for the line. Multiple viewpoints and uncertainties remain regarding the mechanics and safety of the lifting process.

Contextual Notes

Participants mention the need for diagrams to clarify the setup, indicating that visual aids may be essential for a comprehensive analysis. The discussion also highlights the importance of considering the hinge's sturdiness and the overall stability of the tower during the lifting process.

Don Wiley
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Hello folks,
I am new to the forum and have read threads on different topics that have help me out with problems with my projects. Each of the threads I read everyone was helpful and friendly, so I decided I would try with one of my own problems.

I read one thread that has given some of the info I need but not all. What I have is a 60' antenna tower triangular shaped weighing roughly 300 lbs. The base is hinged onto a cement base footing roughly 18" by 18" by 36". I am trying to determine the best location on the tower to attach my line to pull the tower up. I may be using the formula wrong but this is what I get: 300 * (30/7base section height) = 1284. My questions:

If I move the location to say 25' or 20' will this formula hold?
When a pass the 40 degree mark raising the tower does this weight decrease as well as the line tension?

Thank you,
 
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Don Wiley said:
I am trying to determine the best location on the tower to attach my line to pull the tower up.

What's happening at the other end of the line? Are you holding it in your hands? Do you have room to walk along the ground as you pull the tower up ? - or must you stand still ?
 
Stephen Tashi said:
What's happening at the other end of the line? Are you holding it in your hands? Do you have room to walk along the ground as you pull the tower up ? - or must you stand still ?
Thanks for your response. I have a 3/4 ton rope puller I am using to pull the tower up to the house bracket. The 1/2" rope is three strand rated for 6,500 lbs. On my roof there are two antenna tripods I plan on using a pulley on each to guide the rope to the other side of the house, where I plan on anchoring the other end of the puller to a large tree. There is room for someone to walk beside the tower but I was hoping the puller would be sufficient enough, but I need to lesson the side to side movement of the tower if I can.
 
Don Wiley said:
On my roof there are two antenna tripods I plan on using a pulley on each to guide the rope to the other side of the house, where I plan on anchoring the other end of the puller to a large tree. There is room for someone to walk beside the tower but I was hoping the puller would be sufficient enough, but I need to lesson the side to side movement of the tower if I can.

To do a mathematical analysis of the problem would require diagrams of the set-up, or a very detailed description.

Can you simply experiment with various schemes for attaching the line - without breaking something in the process?
 
Don Wiley said:
but I need to lesson the side to side movement of the tower if I can.
How sturdy is the hinge against side-to-side movement? I'd think you would want 3 lines for pulling it up, and at least 1 line for slowing and stopping it at the top. Raising large antennas takes positive control at all angles (don't ask me how I know this...). How does the antenna get stopped and locked in the upright position?

https://i.ytimg.com/vi/jHfyrookXzc/maxresdefault.jpg
maxresdefault.jpg
 
What is the height above the ground of your two pulley connection points?
 
JBA said:
What is the height above the ground of your two pulley connection points?
Hi all,
Thanks for all the questions. It helps to think the process through.

To begin the hinges are 1/4" think flat steel which is 1 1/4" wide and 36" long. There will be a steel plate on each side of the base tower section legs. I have debated getting 3/8" think steel or thicker just to make sure. The hinges are almost 3" above the top of the footing.
I was thinking that some of the other questions asked would be better answered with some pictures and diagrams. I'll put that together tonight and post it for everyone to take a look at. It is said a picture is worth a thousand words. Thanks again and standby for the pictures.
 

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