1. #1
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    Default Ladder Gin Max MA question

    When using a ladder gin, what is the recommended MA? I was told 2:1, but have also heard 3:1 is acceptable. Also, considering vector forces, is it the same as tripod?

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    Ok, I'll take a nibble and risk getting caught: Why would there an MA issue here?

    There's an old thread "Aerial ladder as High Directional or Crane" on page 2 of this forum. Check out my post to the thread on 05-02-2011 with an attachment. The results in the attachment show that the force exerted on the tip of the ladder actually decreases with increasing MA.

    Please email (davey@cwmr.org) me if you have questions.

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    By heck your right. I feel silly now for asking, I should do my homework before posting
    Thanks for correcting me.

    Frictionless system.

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    FYI, your 4:1 is actually a 5:1
    I used to be DCFDRescue 2. Forum changover locked me out.

    www.rescue2training.com

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    I'm gonna crawl under a rock now...

    Corrected drawing:
    Attached Images Attached Images  
    Last edited by MichaelXYZ; 02-22-2013 at 01:02 AM.

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    More clear images...

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    Quote Originally Posted by MichaelXYZ View Post
    I'm gonna crawl under a rock now...
    It's all good...

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    I thought I should finish off this tread with tying off the guy lines of the ladder gin, this is how we do it.

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    Why tandem prusiks? Why not just one?
    Dave

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    Tandems are not needed, not sure why I used em in the drawing. Brain fart maybe.

    I tried to upload a corrected image, but I have seemed to have exceeded my image quota...
    Last edited by MichaelXYZ; 03-15-2013 at 02:25 AM.

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    Random question to raise this thread from the dead.

    Is there a limit to the height a ladder gin can be or a guideline to the angle the guy lines should optimally be at in relation to the ladder?

    As far the ladder height, can I extend say a 24' ladder its full capacity and go to town? Or even a 35? (granted I am assuming raising the ladder off the ground, especially a 35' would be extremely difficult and time consuming)

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    The ladder angle should be 70 degrees, the guy lines should be 45 degree. As for ladder length, all my Ladder system manual say is that 12-16' is recommended.

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    A shorter span like 12-16' would obviously produce massively less leverage at the base but I've seen photos of a ladder gin that had to be almost 24'

    A 24' ladder here is rated for 400lbs and a 35' is 500 lbs but I don't know if they only applies to a straight axial load on it.

    I'm curious if a tip load of potentially 400bs would compromise the ladder?

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