Removable and transportable frame for hoist

 

hi, for a farmer friend of mine I need to make a frame to hook a winch to transport disassembled on the tractor trailer. like the swing portal
measures 8 feet high about 2.50 meters, 8 feet wide must pass through with the tractor trailer and on it hook the winch and lift the weights, maximum capacity 500 kg thanks. any suggestions. the stand must be supported on the ground without wheels. it should be light, easy to handle and easy to transport and assemble what materials do you recommend I use? thanks

 

http://i42.photobucket.com/albums/e327/ice4me/Mobile%20Uploads/IMG_20141025_151138_zpsoyhvmfwp.jpg

 

Your best choice from the ones you show is the 4th from the top. with the angle braces at the bottoms of the posts and the gussets where the cross beam attaches. To make it a break down frame weld the socket or bolt flanges to the cross beam so it will slip or bolt onto the vertical posts. This will be the strongest and easiest to erect.

I did NOT watch the video, the still shows poor understanding of basic structural construction.

Frosty The Lucky.

thanks for your kind advice I will treasure your suggestions, thanks. as measurements I refer to the pillars and the crosspiece how would you do it thanks?

my friend saw the photos of this wooden easel and would like to make a similar one but in iron for work in the countryside thanks

Build it wide enough to drive between the posts with whatever you're loading/unloading and high enough to load / unload the largest thing you anticipate and clear the deck by say 5-10CM.

An A frame, either wooden or steel will sink into soft soil, the heavier the load the harder the soil needs to be. 

The steel A frame with a trolly won't safely lift nearly as much as the wooden one in the pick below it. The wooden A frame is much better designed and built than the other one. A length of lumber say 5cm x 20cm attached between the feet of each A and long enough to extend maybe 30cm beyond will prevent the legs from spreading under a load and spread the weight over a large area.

Could do the same general thing with the steel A frame by pinning the feet into large angle iron spreaders. 

Frosty The Lucky.

thanks for the advice sorry if I bother you a drawing with 4 measurements, the material I take tubular box or profiles type H I or l t thanks. the suggestions I read at 3/ of the height to avoid the zipper being created in the knot and the right angle being closed?? thanks

I'm sorry Angiolino but I'm not clear what you mean by zipper created in the knot. 

Darn translation programs make this difficult but you and I have practice at this don't we? 

Square 100mm or rectangular, 75mm x 100mm tubing is good. it's more than strong enough for the legs if all you're lifting is 500kg. It still needs a spreader to keep the legs from spreading so all the forces aren't concentrated where they come together at the top. The spreader can be pretty light stock seeing as it's only going to be under tension (stretching forces) which is steel's strongest. 

The beam across the top needs to be a bit stronger because it's bridging the space between the legs. 500 kg on a span of 3m isn't too bad, you could get away with doubling the square or rectangular tubing and it's be more than strong enough. By doubling I mean vertically, one on top of the other. Or better still an I beam say 100mm x 200 or 300mm and it can be fairly light weight.

The tricky part is making it so it comes apart easily but is secure when assembled. 

Right now I like a saddle at the top of the A frame legs. I'll have to think about easy fast assembly / disassembly. 

Frosty The Lucky.

thanks in the beam column node I was referring to "the support legs I was saying that connection point should be reinforced so that the corner does not close like a hinge like a door opening, I should put some gusset bolts there to reinforce it some sheet metal triangles in the book would go at 3/4 of the height as in the photo of the wooden easel thanks anyway for the good advice we will update each other thanks.

hinge constraint

 

I don't know quite what to say about those videos, they seem to be more about selling the software than a useful set of instructions for building an A frame gantry. There is so much spinning around of the view it's unwatchable. Even though the translation to English was good there was so much techno babble and so disarrayed I muted it within minutes. The fellow narrating the video sounds like someone who doesn't build things so he's going into intimate details that don't really matter on a structure under this little stress. 

You only want to lift 500kg. on a span. You can look up the correct beam in a book at the metal supply. 

Also I thought you wanted it to be easy to assemble and disassemble. Aligning and bolting this structure is NOT as easy as it looks. Putting an alignment pin between the beam and bolt plates on the legs will make it much easier and faster. 

I suggest you look for a less complicated video, how to. Something not demonstrating the latest greatest cad cam software. Find one made by someone who builds things from structural steel. It will be a LOT less confusing.

Frosty The Lucky.

 

yes, maybe a scissor system would be needed to make the modular structure dismountable and transportable like children's constructions, the sturdy but light and easy to transport Meccano, thanks again, I'll think about it

 

 

 

 

Boy, the "portal" in the video is very far from what I'd consider a "break down" unit. It looks like you'd need a portal to set that one up. 

Something to keep in mind is building a break down portal means it will be more complex than one that is welded or bolted together permanently. 

A light weight version of the one in the bottom pics looks good to me even without the angle brace between the beam and legs. The end plate on the beam would make it much easier to erect as it acts like a stop aligning the other bolt holes. 

Frosty The Lucky.

thanks how would you do it? could you insert the right materials and the measurements considering the size of the reducer, hoist and trolley I have to make a compact but easy to handle portal underneath there will be the body of a vehicle not too big and bulky nor too small useless and not functional thanks. sorry if I bother you.

Hauteur : 3.50m Largeur : 3.17m

I don't have any drawing software on my computer, all that's available is renders in 3D with shadows, landscape and generally useless junk and useless for good mechanical drawings. I haven't had a drafting board, T square and triangles in years. I don't know what you want to load nor into what kind of carrier, truck, trailer, or? Even if I did I could only give you sketches with approximations for dimensions. 

Does it need to be on wheels or are those just the pics you're showing? If it's on wheels you can roll it out of the way and maybe not need to build a break down portal. That would simplify it greatly, you could just build it and use it. 

Build it enough wider than the largest vehicle you're going to back under it so a mistake backing a trailer under doesn't hit it. Maybe 1m wider. 

When YOU calculate the height of the portal don't forget to add the trolly (if you use one) and the hoist mechanism, hooks, etc. You'll be amazed how long a coffing hoist, trolly and connecting shackles is. The "coffing hoist" a chain hoist that can NOT drop the load, it will NOT move unless pull the chain. The one I own when the lift hook is sucked up tight into the mechanism is still probably at least 40-45Cm from the top ring to the hook, the trolly will probably need to be 20-30cm from the rollers to the hook. 

I have no idea what these things measure in Italy, you can find out much more easily than I can so that's on you.

Were I building an A frame portal for someone I'd at least triple the price for building one that breaks down. How are you going to stand it up or lay it down after assembling / disassembling it?

Making one that the legs and beam bolt together is pretty simple but making it "easy" to break down is a major pain in the neck. Easy if you have a fork lift but if you had a fork lift you wouldn't need the portal. Think about it, how are you going to hold the legs up while you lift and position a 350cm+/- beam AND align the bolt holes? Wheels on the legs would make it a nightmare! Call a steel supply and find out how much the top would beam weigh, don't forget to add the weight of the trolly, you can hang the hoist after it's assembled and standing.

This is a much more difficult project to do right than you think. 

Were I building the thing I'd charge enough to hopefully send the person wanting it to someone else.

Frosty The Lucky.

thanks for the valuable suggestions, I can find the beams for the crosspiece among the offcuts of a metalworking workshop in the area, the problem would be to make the side columns or the A or the inverted T, size them well to avoid them from lying down or breaking like a house of cards thanks again sorry for the inconvenience I'll think about it thanks

You're welcome angiolino. If you make the bottom of the A a minimum of 2/3 the portal's total height it should be plenty stable in use. 

Frosty The Lucky.