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Thread: Lifting eyebolt load limit question

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    Bill D is offline Titanium
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    Default Lifting eyebolt load limit question

    I may have some bad information but. On a 13" Harrison lathe there is a 12mm? threaded hole for a evebolt to lift the entire machine. Looking online an eyebolt of that size is rated at about 600-880 pounds, I forget the exact conversion. Problem is the lathe weighs at least 1,300 -1,500 pounds. What am I missing here? Are there supposed to be some other lift points at the same time?
    Bill D.

    this may be the reason that the threaded hole was dropped in latter years

  2. #2
    wippin' boy is offline Diamond
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    mcmaster carr says 2270 lbs for a forged steel 12mm

    link > http://www.mcmaster.com/#catalog/116/1483/=a2orb7

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    burchdb is offline Aluminum
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    I have a Harrison AA 13" and I have the eye bolt that came with it. I did use it to lift the lathe without problems. I only lifted it a bit to put dollies under so I could move it.

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    bridgeport is offline Cast Iron
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    I am a blacksmith, and sometimes forge eye bolts. Many years ago I made some using 3/8
    hot rolled mid steel using the method of welding the ring first and then welding the extension onto the ring using a flared lap weld. The other standard method is to use larger stock, punch the hole, drift it, and then draw down the extension. I brought both types over to the local university materials testing lab, and put them on a hydraulic machine designed to pull metal bars apart to verify strength and elasticity. It was many years ago, and I do not remember the exact numbers,
    but failure occurred at a much higher poundage than I had expected, as I recall it was well over a ton. Based on that experience, I would guess that a modern manufactured 12mm eye bolt would likely fail at a much higher poundage than its stated rating.... perhaps double?
    In any case, eye bolts really are quite strong.

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    Bill D is offline Titanium
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    I had looked at Mcmaster carr. I could not find the metric eyebolts just American thread. Thanks for the link
    Bill D.
    PS: I decided to email Harrison and ask them what the thread is. Don't know wh yit oo kso long for me to realise that is the way to get the real information.

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    Limy Sami is online now Diamond
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    Gary E is online now Diamond
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    Just because you see a tapped hole somewhere in the machine does not mean it's for lifting THE INTIRE MACHINE !!!!!..... could be for just that casting.

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    burchdb is offline Aluminum
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    Bill, Its M16X2 thread with a max. capacity of 630KG/1390 lbs
    Attached Thumbnails Attached Thumbnails imag0080.jpg  

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    burchdb is offline Aluminum
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    Quote Originally Posted by Gary E View Post
    Just because you see a tapped hole somewhere in the machine does not mean it's for lifting THE INTIRE MACHINE !!!!!..... could be for just that casting.
    My manual shows the lift eye bolt exactly as I have.

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    Gary E is online now Diamond
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    Quote Originally Posted by burchdb View Post
    My manual shows the lift eye bolt exactly as I have.
    Then go ahead... why are you asking questions here?

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    burchdb is offline Aluminum
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    Quote Originally Posted by Gary E View Post
    Then go ahead... why are you asking questions here?
    Excuse me!

    I'm trying to answer Bill D's question as best I can since I have a similar lathe

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    Clive603 is online now Titanium
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    Quote Originally Posted by Gary E View Post
    Then go ahead... why are you asking questions here?
    Because he doesn't have a feel for size'n strength when it comes to this sort of thing. Unless you are used to loads and lifting stuff rated in the (say) 1/2 ton to 5 ton range always seems way too small. I have some purple (1 ton rated) straps which, to my eye, look about up to holding things on a push bike carrier! Most ordinary guy guesses on strength are related more to stiffness in bending, e.g. fork lift forks, than pure tensile strength.

    12 mm sounds small though. More usual is 5/8, 3/4, 7/8 range. Big worry is potential thread damage or paint blockage problem. Tend to prefer the Colchester system of a nice steel block clamp to fix to the bed at the indicated place with the eye screwed into it. Presumably at factory or first move 'cos I've never seen a block sans eye.

    Clive

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    Bill D is offline Titanium
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    I am asking here because I am thinking about buying a M300 lathe. If I do buy it I would like to bring the right equipment to lift it. And the answer of 16mm instead of the 12mm I had read about makes a lot more sense because a16mm eyebolt can be rated to lift the lathes full weight.
    Bill D.

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    Greg White is offline Titanium
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    Are we going to talk aboot installing a Eyebolt correctly?
    Gw

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    jim rozen is offline Diamond
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    Nah, just wrap a couple turns of heavy rope 'round the lathe, and clip onto that.
    It'll be fine.....

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    pistonskirt is offline Hot Rolled
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    Quote Originally Posted by Bill D View Post
    a 16mm eyebolt can be rated to lift the lathes full weight.
    Bill D.
    From memory the eyebolt thread in the top of a Bridgeprt BR2J (around 2,000lbs) is 5/8", my first one was delivered swinging rather wildly from the eyebolt on the end of a hiab crane, I had been sufficiently unnerved to subsequently check the ratings of such a forged eyebolt & was both relieved & surprised by the rated capacity.

    regards

    Brian

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    wippin' boy is offline Diamond
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    Then go ahead... why are you asking questions here?
    what an old bitch!!

    use the single eye as shown in book
    throw in a couple safties up to the main hook with a little slack incase something gives


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    bob ward is offline Aluminum
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    Even a lowly 4.6 grade M12 bolt with 240 Mpa minimum yield strength is good for 1.9 tonnes or 4200 lb at failure, a 5.8 grade should fail at 8700 lb.

    One of those McMaster-Carr eyebolts with a working safe load of 2270 lb has safety factors coming out of its backside.

    A 16mm bolt would definitely look a lot more reassuring.

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    Bill D is offline Titanium
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    Brian, a 16mm bolt is just bigger then 5/8 so that makes me happy to hear it ft aBP.
    Bill D.

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    Cool Chains is offline Plastic
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    Default Lifting Eyebolt Load Limit

    Bill, a swivel eyebolt will lift 1650 lbs at any angle and 4400 lbs at a straight pull. Also include that a standard eye bolt has to be de-rated once it is not being pulled in a straight direction. Per published standards any angle over 5 you have to de-rate the working load limit by 45% and de-rate it 75% if it is past 15.

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