Floor Hoist Plans

Structural engineering is not my field but my immediate concern since you want a portable rig is the floor compression. You may be able to find a portable rig that can be placed on a sturdy concrete floor but what will happen when you assemble on two inch thick asphalt or just plain dirt.

all good points, most of the time i expect it to be out in the field, dirt, and so under the 4 feet I would need to put pads or cribbing.

There are several basic types, so a sketch might help; to mention two:
-Gantry? (Basically an I-beam with A frames on each end, resting on wheels).
-Engine lifter? (A U-frame that wraps around the front of the vehicle, with an upper arm extending over the equipment to be lifted).

I will work on the drawings, but a quick visualization would be, 1) looking down from the top it looks like a capital "H", 2) looking from the side its an upside down "T", 3) from the front it looks like an upside down "U". I haven't put my mental plans down on paper yet just looking for some advice given the 5"x5" square steel tubing Ive got.

Thx

Hi spacecannon,

You need to make it look like a capital A from the side - ie a triangle, otherwise the bending moments on your upright and base legs will easily exceed their capacity

Wawaus,

Thanks for the suggestion, but I've done an "A" frame type and was hoping to try something different.

Spacecannon

Excellent description. If the top cross beam is long, somebody should do a calculation on it. The rest of it sounds plenty skookum, but beware that this is only a guess.

Tornado,

Yes, I agree, thx

Spacecannon

Agree fully with #10..

You also need to to mount a gusset below the crossbeam at each end, otherwise the sides will tend to spread outward under load. Such assembly can be bolt-on for ease of portability.

Sorry to state the obvious, but DO NOT use the 5x5 tube for a crossbeam ....

Is it worth doing this when an off-the-peg design comes with its own load test certificates and an easy assessment route for the Engineer/Surveyor from the company that provides failure and collapse indemnity insurance cover?

I would go with certified if i were using it commercially and if i had the money, instead i have the steel, tools, skill and time.

Hey spacecannon, a pre-fabbed gantry crane will most likely be your best bet. By the time you purchase the steel and caster wheels, and then fabricate it, you will spend more than an used one in good shape.

Check out Ebay and Craig's List for used gantry cranes. I see them advertised all the time. Most of the time the selling cost is reasonable.

[last year I looked into designing and fabricating my own, but when I calculated the cost of steel it was far cheaper to buy either a new or good used one.....of course I was planning on a 18 foot high crane with a 10-foot span fully capable of lifting 4 Tons]

I'm sure you will find DIY crane building plans online, but be prepared to pay for them. If you can cut and drill structural steel + are a good welder, then it can be done.

Good luck!

CaptMoosie!,

Thank you for the advice, and i agree with you, however I have this steel left over from another project and a 10 ton chain hoist with nothing to hang it on, with a 5 ton crane scale. Last years project was fun, but unsuccessful. We drove posts into the ground 8 feet and then measured what it took to pull them out, it was for a solar farm mounting frame. Ultimately the utility company rejected our application, even at 10 cents a KWh, they just don't want to loose their monopoly. The locals would buy it but the Utility wont let use use the power lines.

Anyway, your design sounds really cool, did you put it to paper? was it portable easily dissembled?

Thx Spacecannon

Hey spacecannon, to answer your question, no I didn't commit the design to paper. However, the finite element analysis for several different crane designs (jib crane, gantry crane and tri-pod) still resides in my PC. I also have the print outs stored somewhere around here, but good luck trying to find them in a hurry as I'm in the middle of rebuilding a good portion of the house and everything's in storage boxes.

The most promising design was a gantry crane. I had planned on lifting fabricated trusses (made of built-up 6-inch 18 Ga. light gage steel wall studs....ie, box sections)together with the columns. The overall height is in the vicinity of 16 feet.They're for my upcoming 2 story tool shed/storage building that'll have a 2nd floor. Also, the roof will support my arrays of encapsulated glass solar collector tubes.

In the end I decided it would be better for me to purchase a pre-fab gantry crane or a good used one that can extend up to 19 feet height or so. Check out Ebay or northerntool.com. Maybe you can copy good design if you know what they used for the structural elements and connections.

Bummer about your electric company tuning down your PV solar application! I thought that Calif. was in the forefront regarding solar installations!? What's the story there?

We installed 7.56 KW of PV solar on our roof a little over 1.5 years ago...love em!!! Originally, I want to install them on pole mounted array frames with tracking, but the cost would have been prohibited and the solar installer wasn't keen on me installing the poles and foundations (as vs. them doing it...for more bucks too), even though I'm a PE and fully capable DIY'er. Go figure!

CaptMoosie,

Thanks for your input.

Most California Utility Companies are happy in their monopolies, oh you can put one on your house, but if you want to produce electricity on a commercial scale and sell it to them like the law requires then they turn you down or stall you for years. See there was this little clause in the law that said they dont have to let you bring your electricity on line if the line is too congested and the law leaves it up to the Utility to decide if the line is congested. The major point that was missed is that if some solar comes on line then some coal comes offline, but the politicians dont realize this and let the Utilities get away with this B.S. excusse that the lines are full.

GAs to all thanks

Spacecannon

Do you mean hoist or crane? We need your ideas so we know what you are lifting, whether and how far and in which direction (N<>S only or N<>S and E<>W) you want to move it.

Your last paragraph is frightening!, any extension is likely to provide the worst design case.

I think you need self raising portable gantry crane. In this crane you can dismantle the legs and raise couple of legs on each end with help of pulling and lifting machine.it has "I" for supporting Electric Hoist or manual Chain Pulley block with travelling trolley. Electric Hoist will be too bulky to install.Please see this link:-

http://www.abmfasteners.com/downloads/Gantry%20Crane.pdf.

Suresh Sharma,

Ok, that is one cool self raising gantry cane, I have to admit that raising has been the biggest problem with my "A" frame. That was so cool Im going to try to redo my design using the 5" square tubing in this configuration.

GA, thx, and yes I'll ask into the price of the one you suggested.

Spacecannon

When I hear floor hoist I think automotive application. Is this what you want to use it for? If so then there are several out there that are very portable.

CR4 Admin: Replaced broken link to single product with a link to all car lifts on North American Auto Equipment's website.

Even if this is not your app then maybe it can be used as a design model and altered to fit your needs.

Good Luck.

Mechanic,

thx, but not what Im looking for.

Spacecannon

Take a look at www.spanco.com for some ideas. My company represents Spanco and we would be happy to sell you a set of legs for you to attach your beam to. Start at Spanco, and let me know if you would like more assistance.

MrMikeB,

Ok, Spanco was impressive, and i will not be able to afford one of those this year, however their specs are so detailed that I think I have found my plan sets.

Thanks GA

Spacecannon

I'm glad that their website helps. Let me know if I can assist with beam sizes and measurements and don't rule out purchasing the legs. Spanco is very affordable so you might be surprised. (I'm not a salesman, although I know it sounds like it.)

Greetings All,

I think I have found a beam to span the top of my portable Gantry/hoist. Its off of a manufactured home frame. The width of the "I" beam is 3 inches and the height is 12", the thickness is 5/32 mild steel. I can get 1 piece 16' long or 2 pieces 14' long.

My question at this point is if the 16' piece is supported on both ends, how much weight can I hang in the middle (8' center point) before it collapses, will I reach my 10 tons or do I need to weld the two 14 footers together, side to side, ("II"), to get a 10 ton lift?

Thanks Spacecannon

I don't have the information to do the calculation you request, but welding the two 14 footers one above the other, flange to flange will give a much greater lifting capacity than side by side,

The vertical distance between the outer flanges is critical to the strength.

ok thx GA

Pure instinct only....

I wouldn't attempt 10t on the beam you describe...5/32" is lightweight...even 5t may be a risk , but I can't prove it at the moment (no pun intended).

The longer the beam, the lesser the load the beam will support at it's centre.

Hang in there..(pun intended)

Hilton,

GA thx for your opinion.

It is very small beam for 10 Tonne load supported at 12 ft span you will require min. 24" Ht. and 10" width "I" beam. With 12" ht. "I" beam you can lift max. 1 Tonne.

Sharma,

GA thx for your opinion.

Captn,

GA, thx.

What am I doin? I dont know, "crazy" is my hobby. We used to move alot of heavy things, and I cant get explosives anymore to help move the boulders. I've got the steel and I need to know what I can do with it.

Lets approach this differently. The I beam was welded together by a mobile home mfgr. about 5 years ago, the steel is 5/32 thick with no marks on it, so consider it to be the cheap mild stuff. It was supporting a very heavy trailer, 2x6" walls with 1/2 drywall with 10' foot ceilings, but they also designed it to the minimum load cause they were cheap. Now this is a narrow "I" beam, 3", I know that is not good and will probanly have to put 2 beams together side by side, welded. So I might not get 10 tons, but if I narrowed the span to 8-10'...

This is just a back yard, jury rigged, contraption that I know can kill me, but having a lot of experience in dangerous jury rigging and have learned to stand far back.

Note, I know the 5/32 top and bottom on these "I" beams is too weak to support a trolly, so we are talking about a point load, or I can put a couple of feet of 1/2" steel plate under the point load to distribute the weight.

So what do ya'all thick the max point load is for an "I" beam like this would be with a span of 8-10 feet? NOTE: NOBODY'S OPINION WILL BE HELD AGAIST THEM IF IT ALL GOES WRONG.

Spacecannon

PS; did I metion I was building a hydrogen filled blimp.

Here in India we call it "Jugad" something crude made by experienced mechanic which can serve the purpose economically to finish the job. Of course it is risk taking job but normally experience pays off.

How do you pronounce "Jugad", is it joo-gaad, or yu-gahd, or .....?

Simple Ju gaad.

Thx Spacecannon

Instinct really kicking in now...

"a couple of feet of 1/2" steel plate under the point load to distribute the weight"

The 1/2" plate is a fair idea, except that the load rating of the beam will depend on the weld quality .... I hope I understand correctly, that you will sling the hoist over the beam, and not underneath it ??

If you plan to cut an eye in the 1/2" plate and hang the hoist from there, DON'T !

Under load, the plate weld may tear away from the 5/32" material. In any case, I like the 'who dares wins' approach, but stand back and keep your cheeks well clenched for any lift > 2,5t.

Yes, over it. The 5/32 will just tear otherwise. yes standing back.