Page 1 of 2 12 LastLast
Results 1 to 10 of 13

Thread: building a gantry crane

  1. #1
    Join Date
    Mar 2003
    Posts
    1,209

    Post building a gantry crane

    I am thinking of building a gantry crane similar to this one which is found on the mcmaster website.


    I am going to make it about 9-10 feet wide and 6'6" high to just high enough not to bash what are left of my brains out.
    I will put a track on the floor,angle iron or what i can find so it will move up and down the shop out of the way.

    What is a suitable method of attaching the I beam to the up right tube?

    I was going to weld a 1/2 plate to the top of the tube and boltthe I beam to that ,but i wonder whether i should drill through the i beam or straddle it
    - ie plate on top and bottom and bolts out side the i beam?

    Clear as mud ?

    Cannot find any similar cranes to look at around here.

    thanks

    just cut an pasted in supports as suggested
    found some 4.5 by 14" plates bout 1.25 thick for top of tube.


    [This message has been edited by thistle (edited 07-13-2005).]

  2. #2
    Join Date
    Sep 2001
    Posts
    102

    Post

    I made mine with a 6" H beam on top and just bolted to the first flange. There is a 45 degee 1 1/2 sq tube guset on the same plate about a foot from the main post.

    ------------------

  3. #3
    Join Date
    Nov 2002
    Location
    Kenosha, not the pass the other one
    Posts
    2,448

    Post

    Definetly a gusset is in order on the outboard side of the verticals. A while back I was thinking of building one of these out of wood for picking loads out of pick-ups or trailers. But if you do build one of these I think I would get the trolley for the hoist first and size the beam to that
    The optimist says the glass is half full, the pessimist says it's half empty. The paranoid in me says somebody put a hole in it.

    Remember pessimists are at heart opptomists. They know things can and will get worse.

  4. #4

    Post

    Without doing any engineering calculations -

    What is the load on the gantry crane? That will control how big the I beam should be.

    Do not size the height so it will clear your head. Size it to the minimum overhead clearance your shop has. Murphy's law says you will need an extra three inches of lift within 6 months otherwise.

    Forget the tracks. Put four big casters on the bottom so it can be moved all around the shop. Don't forget a brake, or one day it'll roll down the driveway to the street with something heavy.

    Use bolts through the flange to secure the upright. Make the plate on top of the column at least as thick as the flange of the beam. At least four bolts per column. Sizes of 3/4" on up may be sufficient, but the loads on the crane will control. Diagonal braces are a good idea.

    You might cantilever the beam out on one side. That side can then be used for a hoist to move heavy things on or off machine tools where there is no clearance for the whole crane.

    As usual, consult a qualified engineer licensed in your state if you have any questions about the safety or capacity of your system.

    Karl

    ------------------
    At a certain point in the course of any project, it comes time to shoot the engineers and build the damn thing.
    At a certain point in the course of any project, it comes time to shoot the engineers and build the damn thing.

  5. #5
    Join Date
    May 2003
    Location
    52N 122W Western Kanuckistan
    Posts
    40,418

    Post

    Here is a useful piece of freeware for calculating loads on beams and determining deflections.

    http://www.geocities.com/richgetze/
    Free software for calculating bolt circles and similar: Origin now settable to bottom left! All values positive. Click Here

  6. #6

    Post

    I built something close to that but used heavy wall tubular steel for the frame and also accross the span instead of the i beam. I joined the top span to the sides by taking the next size smaller tube (which slides in real nice in the larger tube)and built an ell. I made the ell piece long enough that I can extend the height of the frame in need be and also can widen the frame too. Having said that if you are using the i beam and tubular uprights I would probably weld a long stub on the bottom to the i beam and slide it into the upright with a a series of holes to adjust for height if you need to go higher. With limited space I can take mine a part real easy for storage.

    Brent

  7. #7
    tattoomike68 Guest

    Post

    6'6" is not very high buy the time you add a chain hoist or winch you lose room.

  8. #8
    Join Date
    Jan 2005
    Posts
    264

    Post

    thistle,

    I've thought about building one of these as well, but a telescoping version, kind of like this one:

    http://www.harborfreight.com/cpi/cta...emnumber=41188

    I imagine that using several large bolts, one each side to set the height would be sufficient for a pretty hefty load, but I haven't done any calculations on it yet. It' sure would be nice to having an adjustable one I would think. It would be a pain to adjust up and down, but I think you could probably put bottle jacks under each pillar to help adjust the (heavy) I-beam up and down when necessary, depending on how heavy it is. Just thinking out loud here.

    Anyone else ever use one of these telescoping ones before ?? How much of a pain are they to adjust up and down?

    Chad

  9. #9
    Join Date
    Mar 2003
    Posts
    1,209

    Post

    I dont have the head room in my dungeon to go lower than that , but if i could find some pipe/ tube whatever that would fit inside then it might be a goo idea to make the thing telescoping.

    Harbout Fright sell long reach 8 ton jacks for the engine hoists fairly cheaply .
    a pair of those could mounted one on each side and connected together to raise the thing up.

    bought one a while back but dont trust it to maintain a load, and i dont get underneath it .you would have to raise and the lock the thing off.

    [This message has been edited by thistle (edited 07-13-2005).]

    [This message has been edited by thistle (edited 07-13-2005).]

  10. #10
    Join Date
    Jan 2005
    Posts
    264

    Post

    <font face="Verdana, Arial" size="2">bought one a while back but dont trust it to mantain a load, and i dont get underneath it .you would have to raise and the lock the thing off.</font>
    thistle,

    yeah, that was my intent -- if the I-beam is particualarly heavy such that it is very difficult to muscle around (when unloaded), the jacks would help lift each side to a point where you could slide the bolts in to lock the pillar in place. Your idea of the long reach jack would be great -- weld a bracket to the outside telescoping section and a bracket to the inside telescoping section, and mount the long-reach jack in between the two in it's closed position. You might want to think this idea through a bit more to see if you could have a couple different mounting positions though (lift -- lock -- move jack -- unlock -- lift -- lock -- move jack, etc.) Not sure how much of a tendency to bind this would create either.

    A linear actuator inside the tube might be prohibitively expensive, but would be a slick way to adjust things as well, provided the the tube was large enough. Ok, the ideas are starting to get kinda crazy, better stop now.

    Chad

    [This message has been edited by webbch (edited 07-13-2005).]

Posting Permissions

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