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  • Advice on Building an Elevator

    Hi all,

    I'd like to tap the collective wisdom and experience of everyone for a project.

    As I get older, I really dislike having to use my Induma turret mill (think BP on steroids) in my unheated garage. I've managed to move most of my machine tools down the bulkhead into my basement except for three large beasts: the Induma, a Van Norman 2RQ (~4,100#) and a 16x60" Axelson (~7,100#). The last two are obviously going to stay put, but the Induma could be moved with some ingenuity.

    The smaller lathes, like a SB heavy 10 turret, were moved down the bulkhead stairs with a winch after being bolted to a 2x12 base. At 800# or so, it was as much as I want to deal with. Even dismantling the Induma, the base casting will probably be in the 1,500-1,600# range by itself. The problem with the bulkhead is that the stairs are very steep - an 8' rise with only a 68" run means there is only about 42" of head room when taking large or bulky items down the steps on skids.

    So the idea of removing the bulkhead stairs entirely and installing a custom built lift or elevator has great appeal for me. Moving something with a pallet jack would be so much easier.

    I've had several ideas that have gotten to the CAD stage, but each has its problems.

    I first thought of a heavy platform (say 2x4x1/4" tubing with a 1/4" diamond plate top), lifted by a center mounted three stage hydraulic cylinder. This would work nicely for the approximately 96" of lift I would need. But how do you keep the platform stable for loads that are not perfectly balanced over the attachment point? I thought of welding
    extensions to the sides/ends of the platform that would then ride inside channels attached to the walls of the bulkhead; but with enough weight off center, those could be wedged and jam.

    I then thought of a custom built hydraulic scissor lift. It would take two or, more likely, three stages/sets of arms to give that much lift. At that point it would need to be over 15-16" tall and take up too much of the vertical space available (unless I want to jackhammer the poured concrete floor of the bulkhead and recess it).

    My current thought is using a wire rope and pulley arrangement supporting all four corners of the platform. It could be powered by a relatively simple motor and chain drive with appropriate gearing. The problem would be coming up with the equivalent of a hydraulic check valve to prevent dropping the load with a catastrophic failure of the drive mechanism (yes, I realize that a check valve would not save anything should a hydraulic line rupture).

    The platform needs to be about 44" x 66" with around 96" of lift. I'd like to be able to raise 3,000# at a minimum. I am certified in virtually all aspects of Arc and Mig welding and have all the welding equipment anyone could ever want or need.

    Yes, I suppose I could just hire a rigging company to do the move for me, but what fun would that be?

    Any thoughts you might have would be appreciated.

    Brian
    Taxachusetts

  • #2
    In 1974 I built a freight elevator at a diesel shop I worked. It was not for people, just parts. I used a gear reduction box and made a drum for the cable. It had an electric brake on the gear box. I used limit switches at the top and bottom and had a hand held up/down push botton box. I used two H beams bolted to the wall with rollers on the elevator to guide it up and down and keep it straight. It's been repaired and modified over the years but has worked just fine.

    Later the insurance company had them close in the elevator with expanded metal and a door at the bottom to keep people out from under it. No body ever was stupid enough to stand under it but at some point someone may have been so inclined. They are still using it as of two years ago.
    It's only ink and paper

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    • #3
      The insurance angle is something to consider. Saying you are going to build an elevator is sort of like saying you are going to invent your own electrical code and wire your house to that code.

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      • #4
        Elevator

        Why not make or purchase an "A" frame crane arrangement to lower or raise the equipment through the bulk head area? Would be a less expensive, easier to assemble and disassemble, and a assure the capacity, among other reasons.

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        • #5
          I have seen several made from old jitney masts.

          They are ussually cheap from the scrapper, bolt them securely to the wall,
          make a platform to go over the forks, add a 110v pump.

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          • #6
            Just go get yourself a forklift mast. Shouldn't be to hard to find one rated for only 3000lbs. You being a weldor you should have no trouble building what would be needed for a frame. The forklift mast will give you the piece of mind to lift what you want I would think. A small hydraulic pump unit attached to the mast and you would be good to go.
            Location: The Black Forest in Germany

            How to become a millionaire: Start out with 10 million and take up machining as a hobby!

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            • #7
              I know a few houses that have elevators installed that operate on mains water pressure.

              The elevator rises in a 'shaft' that is lined with carpet and the elevator itself is a plywood box that is a close fit in the shaft.

              The lifting mechanism is a simple hydraulic ram made from off the shelf plastic pipes, diameter chosen according to water pressure and weight to lift.

              The ram is sunk into a hole drilled in the ground.

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              • #8
                The flat plate worm gear hoists are used around here to lift boats out of the water. Two inch pipe pins into the hoist and is used to wind cables attached to each corner.http://www.boathoistusastore.com/categories.asp?cID=231&gclid=$2&c=215331
                Byron Boucher
                Burnet, TX

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                • #9
                  Some interesting replies so far. Thanks to everyone.

                  Carld: Sounds interesting, but I'm having difficulty envisioning how you used just two H-beams. How are they situated and how do the rollers on the platform seat into them to maintain it level? It sounds like it is capable of lifting more than a few hundred pounds, so I'd be interested in hearing more about your design.

                  Bruce: I'm not worried about the insurance aspect. I would have a keyed lock-out on the thing and it would be removed and the steps being replaced before I sell the place and move south.

                  Gene928: I had considered an A frame and gantries quite a while ago. The location just doesn't lend itself to such an arrangement, however. It would be simpler, though. I'd also considered a jib crane arrangement, and that is still a possibility.

                  Black Forrest: a forklift mast is a great idea that I had not thought of and they turn up all over the place for basically scrap price. Unfortunately, the bulkhead's interior dimensions are too small to allow for such a mast to be installed and have enough room for a standard pallet as well. Did I mention that it's a good idea.

                  Artful: That's interesting. I have about 60psi of water pressure, so I'd need about an 8" diameter pipe. That's a standard size for pvc. However, I doubt that such a pipe could support 3,000# without crushing/cracking. Maybe I could use 8 or even 12" schedule 80 steel pipe instead. Would certainly be a lot simpler than using a typical high pressure hydraulic system. The problem would be finding a way to insert the ram with a water tight seal given that most pipe is welded and has an interior seam.

                  Byron: That's a really interesting website - thank you for the reference. They have some neat engineering ideas - I especially like the cable winders as that is a simple and relatively inexpensive solution to one of the problems I saw with a cable type system.

                  Thanx to all again,

                  Brian
                  Taxachusetts
                  Last edited by H8Allegheny; 02-21-2012, 03:56 PM.

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                  • #10
                    How about four big acme screw rods C/W sprockets and a length of roller chain? Keystone Threaded Products lists some pretty skookum rod and bronze nuts to match. Seems to me that used to be the basis for some car hoists.
                    Duffy, Gatineau, Quebec

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                    • #11
                      Brian, I think aluminium pipes as used in irrigation systems are extruded and have no internal seams. If the PVC pipe can stand the 60psi then I dont think putting a compression load on the end of it will put any compression forces on the pipe.
                      Last edited by The Artful Bodger; 02-21-2012, 09:11 PM.

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                      • #12
                        A couple years ago a friend wanted me to help him design and build a freight elevator. The situation was such that you had to roll carts up a bit of an incline to get onto the floor slab from outside, so extending the incline to get the carts up another 2 or 3 inches wouldn't have been a big deal. The extra few inches would have been the floor of the elevator. From inside the building, you'd have to roll a cart up an incline to get it onto the elevator floor, but if you wanted to roll the cart outside, you'd have to go up onto that floor, then down the other side. The longer the inclines the less the slope, so we came up with the idea of making the inclines part of the elevator. They would hinge up and become sides, preventing stuff from rolling off when you were hoisting it. The elevator cage itself would have been a rectangular box with four corner posts, fully welded etc.

                        Next part of the design was to have a rectangular frame which would bolt to the upper floor ceiling trusses. Running across the center of this would be a section of steel pipe about 4 inches in diameter, driven at one end by a worm gear winch setup. Pulleys would be mounted at the four corners and each one would have two cables passing over them for some redundency. Each corner therefore was to have two cables pulling up on its corner of the elevator floor. All of the cables would wind up on the steel pipe simultaneously.

                        If each cable was 1/4 inch diameter, it would need about 2-1/2 inches of space on the pipe to wrap up enough to be able to lift the elevator about 9 feet.

                        My biggest concern was finding a worm gear box that was essentially free of any failure mechanism. I don't think this would be a problem- you would simply use a gearbox with a high enough rating.

                        Where I used to work, we had nothing but problems with our freight elevator. One day I decided that enough was enough, and replaced the entire winch unit with a worm gear box and an induction motor driving the box through a belt and pulleys. This had lots of torque and didn't break down, so that was all happiness. However, after about a year or so it decided that it wasn't self-locking anymore. If you had lots of weight on the elevator, it would raise it up and the motor would shut off, but then it would slowly do an unwind and go down. The worm wheel was driving the worm and spinning the motor.

                        An induction motor has almost no resistance to being turned by an external force, unlike a permanent magnet motor which has at least some self-holding ability. The gearbox I used was from an 8000 lb rhino winch, so I figured it would have been ideal. At any rate we came up with a dog system which locked the elevator floor to the uprights when it was in the raised position.

                        This system used a single cable, which was simple but not really ideal. Over the years, the top of the elevator had bent upwards, pulling the sides in. I don't think that ever was a problem really, but I would have built the thing with some triangulated bracing from the corners to the lift point to avoid having this happen. I know welded joins can be pretty strong, but why force it to work harder than it has to- the principle here is similar to lifting with a sling- the shallower the angle on the sling, the greater is the tensile strain for the same weight being lifted. Any rigger would know this.

                        Anyway, maybe there's some ideas in there that are useful.
                        I seldom do anything within the scope of logical reason and calculated cost/benefit, etc- I'm following my passion-

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                        • #13
                          National elevator code

                          There is a national elevator code that covers elevators, material lifts and so forth. Your biggest issue is your insurance, since they probably won't cover it unless you have permits issued. Local governments are also happy to jump on the review and permit bandwagon as well.

                          I'm a registered professional engineer and had the joys of taking elevators and material lifts through the approval and installation process and want to let you know that it's not much fun. The code is in place because dropped elevator cars are considered to be a major concern for public health and safety. The requirements are very stringent and most localities require a licensed and certified elevator installer to put it in. Most local governments require a design review and approval. They are usually very touchy about an installation and if they find out you've built one, they can go so far as to lock it out, require you remove it, condemn the structure it's in and levy steep fines on top of it all.

                          My recommendation is to not take on an elevator and instead work out a temporary hoist to do the move and then take it down.

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                          • #14
                            There are a number of two and four post hoists available for working on vehicles, maybe one could be dismantled and rebuilt in your building?

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                            • #15
                              if it is just for moving equipment and such. Do a web search for walking hand trucks (I think). Companies that move gun safes use them. They are hand trucks that walk right up stairs. Kind of interesting.

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