would you.....
Close
Login to Your Account
Results 1 to 11 of 11

Thread: would you.....

  1. #1
    Join Date
    Jan 2009
    Location
    midwest
    Posts
    104
    Post Thanks / Like
    Likes (Given)
    2
    Likes (Received)
    4

    Default would you.....

    CALDWELL Portable Gantry Crane, 4000 lb., 8 ft. 6" - 40N127'|'HA90-2-10'/'8 - Grainger

    Use a gantry like this, in this fashion:

    The left upright was moved to the center, creating an over hang of about 50% of the beam. The right upright was chained to the floor using a couple anchors.
    The over hang was then used to pick a 500 pound load and wheel it out of a tight spot....


    Pass or fail? It worked without any incident but it looked sketchy as heck to me

  2. #2
    Join Date
    Oct 2009
    Location
    Olympia, Wa
    Posts
    594
    Post Thanks / Like
    Likes (Given)
    300
    Likes (Received)
    171

    Default

    I can't imagine 500lbs being too much for that crane, in that situation.

  3. Likes hermetic liked this post
  4. #3
    Join Date
    Jan 2009
    Location
    midwest
    Posts
    104
    Post Thanks / Like
    Likes (Given)
    2
    Likes (Received)
    4

    Default

    Quote Originally Posted by Blazemaster View Post
    I can't imagine 500lbs being too much for that crane, in that situation.
    yea..just never saw someone chain something like that a floor... I am used to forklifts and mobility...

  5. #4
    Join Date
    Oct 2010
    Country
    UNITED STATES
    State/Province
    Oregon
    Posts
    4,960
    Post Thanks / Like
    Likes (Given)
    4062
    Likes (Received)
    1786

    Default

    I have more than once set my somewhat larger portable gantry crane (Vestil 3T 10') with the beam overhanging a post by about 2', just out enough to put on a fixed beam clamp and have the chain hoist clear the post. The entire crane weighs roughly 1000lbs, so I have about 500lb (the shifted post doesn't count, but most of the beam does) with better than 4:1 leverage counterbalancing the load on the extended portion of the beam. You can do a 1,200lb lift in this configuration without the far end getting too squirrely, or the shifted post taking excessive load.

    With the 50% configuration, the real issue is the tie-down anchors, because the crane itself is doing much less to counterbalance the load. The 500lb load itself should pose no strength issue to the crane, but you may have to look at the design of the post-beam clamps as they may not have been designed for beam bending in this fashion.

    You can be sure the manufacturer will not endorse the use of the crane in this fashion, so any failures are between the user, the victims, and OSHA.

  6. #5
    Join Date
    Apr 2006
    Location
    Manchester, England
    Posts
    7,975
    Post Thanks / Like
    Likes (Given)
    1116
    Likes (Received)
    4960

    Default

    Have a couple of fat guys stand on the far end by the castors and you're good to go.

    Regards Tyrone.

  7. Likes adama, Derek Smalls liked this post
  8. #6
    Join Date
    Apr 2005
    Location
    Beaverdam, Virginia
    Posts
    7,070
    Post Thanks / Like
    Likes (Given)
    543
    Likes (Received)
    3230

    Default

    Seems real pricey for what it is, but that is Grainger for you.

  9. #7
    Join Date
    Dec 2004
    Location
    uk
    Posts
    14,058
    Post Thanks / Like
    Likes (Given)
    4552
    Likes (Received)
    6696

    Default

    Quote Originally Posted by Tyrone Shoelaces View Post
    Have a couple of fat guys stand on the far end by the castors and you're good to go.

    Regards Tyrone.
    I much prefer counter weight to chain down, chain down especially to floor anchors if they have not been load tested is a far bigger unknown, also height of lift. if your just taking it off floor and spinning it, no one near it, the kinda risks are low.

    In the described setup, just how far in that leg is matters greatly, if at the 1/4 of the way to other leg you should be fine, putting the leg at the half way point, you really want the next size up gantry, sure the legs strong enough, but the beam is at arguably approach design capcity and in a dodgy setup, it pays to have a bit extra margin!

    Whilst its never safe to be under a load, the person that taught me the basics of staying safe kinda made it clear you should not be lifting something if you don't have enough confidence in the rigging to walk under it. That said, if you have a load cell and something heavy, a lot of dodgy setups can be proven and tested as a safe working solution. Theirs no magic, but yes its very much down to you to get it right and its on you if it goes wrong.

  10. #8
    Join Date
    Apr 2004
    Location
    Modesto, CA USA
    Posts
    6,580
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    1068

    Default

    Wallace gantry cranes are designed to overhang at one or both ends. I beleive the trolley can not be rolled past the leg attachment points so it has to moved to the end before the legs are moved around.
    I suppose it is similar to a gin pole crane.
    Bil lD

  11. #9
    Join Date
    Oct 2005
    Country
    UNITED STATES
    State/Province
    Pennsylvania
    Posts
    13,993
    Post Thanks / Like

    Default

    104 postings...

    Would You ???

    Try to compose a proper title ?

    Please try and follow the rules around here, it's not that hard.

  12. #10
    Join Date
    Jun 2004
    Location
    Melbourne Australia
    Posts
    5,458
    Post Thanks / Like

    Default

    Quote Originally Posted by Justsomeguy View Post
    The over hang was then used to pick a 500 pound load and wheel it out of a tight spot....
    You ought to be shot for such a shit title.

    This load, did it have just daylight under it, or was it 6 feet in the air? I like creative rigging. I'd doubt the de-rating of a double end support 4,000lb span would be bothered too much to become a cantilever at 500lb (1/8) at 50% span. I'd note max span of the beam was 9' 6".

    Your only issue is the attachment strength of the anchors. Given you have what is essentially a seesaw, those anchors need to see 500lb across the pair of them. 250lb each. Being lifting there should be a safety factor. Down here it's 6:1. To do it legal. So each anchor should be rated to 1,500lb pull out or concrete failure. Any amount of masonry products that will achieve this. Epoxy grouts etc, that only list concrete failure as its bond strength.

    We need a video of this lift that worries you

    Regards Phil.

  13. Likes tdmidget liked this post
  14. #11
    Join Date
    Dec 2000
    Location
    Coastal Dogpatch, SC, USA
    Posts
    51,238
    Post Thanks / Like
    Likes (Given)
    2768
    Likes (Received)
    5566

    Default

    Closed due to utterly meaningless topic title


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •