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Mitch schiffer
05-09-2023, 7:07 PM
Does anyone know where I can buy hinges to make a jib crane? All I can seen to find are gate hinges when I search on Google.

Jerry Bruette
05-09-2023, 7:42 PM
I looked at Global Industrial and McMaster-Carr and all I see are complete cranes. I'm not sure if you can buy just the hinges. What's your load limit and span? If it's not too heavy or too big of a span you might be able to use unistrut or 80/20.

Mitch schiffer
05-09-2023, 8:14 PM
I looked at Global Industrial and McMaster-Carr and all I see are complete cranes. I'm not sure if you can buy just the hinges. What's your load limit and span? If it's not too heavy or too big of a span you might be able to use unistrut or 80/20.

I was hoping to get 1 ton capacity. I have all the other materials. I didn't think finding hinges would be an issue.

Lee Schierer
05-09-2023, 9:08 PM
Does anyone know where I can buy hinges to make a jib crane? All I can seen to find are gate hinges when I search on Google.

Here is one place: crane parts (https://www.abell-howe.com/product-category/parts/fittings/)

With all the small shops that are closing you might be able to pick up a used one pretty cheap. Look for used industrial equipment dealers The company I worked for bought several pieces of equipment from a dealer.

Tom M King
05-09-2023, 9:30 PM
You can buy some really heavy hinge barrels on ebay. I bought some pretty good sized ones to make hinges for 10x10 swinging shop doors. Mine had 3/4" pins. I added thrust bearings on the bottom hinges. You can get them welded to plates, or just the barrels to do your own welding, which is what I did.

edited to add: These pictures were in my gallery here. I thought I had one of the front of this building finished, but looks like not quite.

Mitch schiffer
05-09-2023, 9:59 PM
Here is one place: crane parts (https://www.abell-howe.com/product-category/parts/fittings/)

With all the small shops that are closing you might be able to pick up a used one pretty cheap. Look for used industrial equipment dealers The company I worked for bought several pieces of equipment from a dealer.

Thanks for that. I did send them a email. Unfortunately you can't just order online.

Bill Dufour
05-10-2023, 12:37 AM
Many use a standard tow hitch ball on top. Some kind of socket just sits down on it like a gooseneck trailer hitch. Big issue is being able to adjust it to be perfectly level. If it is not it will swing by gravity to one position. Do you realize how big and heavy the foundation needs to be? A much lighter design is one post and one leg that rotates around. Sort of a cross between a jib crane and a gantry.
The taller the crane and the longer beam increase foundation needs as much as load capacity. Are you sure you have enough headroom for one?
Bill D

Bill Dufour
05-10-2023, 12:53 AM
Swiped from another forum
"This is a very simple engineering problem. A ton at 12 ft exerts 24000 foot-pound moment (plus something for the weight of the beam) at the hinge,plus the vertical load. If your hinge points are 2 ft apart, then the upper one under static rated load will see about 12,000 lb trying to pull it out of the wall, and the lower will see the same pushing it into the wall. Each hinge has to be designed to carry all of the vertical load, because they will never share it equally.

You need to consider the hinges themselves, also the wall or post if any, the foundation of the post and its behavior as a beam, also the connections between all the parts, the strength of all your materials, forces acting in all the different directions the beam will swing.....AND appropriate safety factors for all the parts. YOUR crane will not fall on MY head but it may fall on someone's."
For wall mounted jibs hinges can be pillow block bearing housings with a bronze bushing pressed in.
Bill D

Ronald Blue
05-10-2023, 8:21 AM
Swiped from another forum
"This is a very simple engineering problem. A ton at 12 ft exerts 24000 foot-pound moment (plus something for the weight of the beam) at the hinge,plus the vertical load. If your hinge points are 2 ft apart, then the upper one under static rated load will see about 12,000 lb trying to pull it out of the wall, and the lower will see the same pushing it into the wall. Each hinge has to be designed to carry all of the vertical load, because they will never share it equally.

You need to consider the hinges themselves, also the wall or post if any, the foundation of the post and its behavior as a beam, also the connections between all the parts, the strength of all your materials, forces acting in all the different directions the beam will swing.....AND appropriate safety factors for all the parts. YOUR crane will not fall on MY head but it may fall on someone's."
For wall mounted jibs hinges can be pillow block bearing housings with a bronze bushing pressed in.
Bill D

Definitely very valid points Bill has shared. Every jib crane I have been around has been attached to the steel H beam of the building. As I recall the strut that supported the end of the beam was four or possibly even 6 feet above the beam at it's attachment point. The higher it is the less the load becomes on the post. There probably is a rule of thumb in play here. Probably an ideal angle or something for the strut. I also recall a couple whether from shock load or who knows what having damaged the H beam slightly. The alternative are the floor mounted jib cranes. They have their own requirements for the base and concrete. Not sure what your specific requirements are so beyond these observations and comments I have nothing.

George Yetka
05-10-2023, 9:47 AM
The jibs I have come across are all on hydraulic cranes to get extra reach and we try to avoid them because they take extra time to setup/breakdown. These are all connected with fabricated pins and brackets.

https://www.youtube.com/watch?v=Cf-mjWQXAjQ for example

Mitch schiffer
05-12-2023, 7:11 AM
Swiped from another forum
"This is a very simple engineering problem. A ton at 12 ft exerts 24000 foot-pound moment (plus something for the weight of the beam) at the hinge,plus the vertical load. If your hinge points are 2 ft apart, then the upper one under static rated load will see about 12,000 lb trying to pull it out of the wall, and the lower will see the same pushing it into the wall. Each hinge has to be designed to carry all of the vertical load, because they will never share it equally.

You need to consider the hinges themselves, also the wall or post if any, the foundation of the post and its behavior as a beam, also the connections between all the parts, the strength of all your materials, forces acting in all the different directions the beam will swing.....AND appropriate safety factors for all the parts. YOUR crane will not fall on MY head but it may fall on someone's."
For wall mounted jibs hinges can be pillow block bearing housings with a bronze bushing pressed in.
Bill D

I have pretty secure post to mount it on. The post is 8x8 1/4" thick steel welded to a w16 67 beam at the top and sitting on a concrete pier. The pier and the beam are braced laterally by the floor system of the 1st and second floor.

Bill Dufour
05-12-2023, 9:58 AM
So you are making a wall mount crane. In that case just use two pillow bushings and a pin at as each hinge mount. Bolt them to the post with a stack of washers to adjust level.
A total guess is one inch or two inch shaft. See second link to do the calculations.
Bill D.

https://www.skf.com/us/products/mounted-bearings/ball-bearing-units/pillow-block-ball-bearing-units/loads

https://www.skf.com/us/products/rolling-bearings/ball-bearings/insert-bearings/loads

https://www.skf.com/us/products/rolling-bearings/ball-bearings/insert-bearings#cid-488583

Malcolm McLeod
05-12-2023, 11:53 AM
Lots of loads to consider: tension, compression, shear, and torque. It sounds like you'll have all.
Welding (if any) should meet accepted standards: ASME, ANSI, AWS (some or all?).
Strength of materials: in the crane components, hoist, pier, column, and (ceiling) beam.
Throw in a designed safety factor.
Line of fire: make sure you and whatever else is under this - or might be - can move or has escape route.
Usage environment: shop, personal/employees, retail = liability.
Add routine inspection.

Please be careful.

(About 20% our company accidents involve lifting & rigging, so we cover it in safety mtgs at least every other month.)

Tom M King
05-12-2023, 12:31 PM
Here's the larger version of what I used for those door hinges.

https://www.ebay.com/itm/293696207503?hash=item4461a87a8f:g:i7MAAOSwt4xfPVk 7

I put a thrust bearing on the bottom hinge pins only because they would be easy to change in the future without taking the whole door down, and one bearing was more than enough capacity for those doors. I would use several thrust bearings for a jib crane. Those doors can swing with a push of a little finger.

Maurice Mcmurry
05-12-2023, 4:54 PM
King Architectural Metals has very heavy duty gate hinges that could be used to provide the swing, combined with parts from an engine hoist could provide lift. It would require a good deal of fabrication. If fabrication is going to happen, I would be thinking of starting from scratch.

Tom M King
05-12-2023, 5:01 PM
This place has some interesting stuff:

https://www.wallacecranes.com/products/jib-cranes/jib-crane-kits/

and even McMaster-Carr

https://www.mcmaster.com/products/brackets/column-mount-rotating-cranes-6/

Maurice Mcmurry
05-12-2023, 7:02 PM
3 point hitch components from a farm supply store would be a good source for parts as well.