How to lift from the center of the bucket

[kebo]

kebo-

Making sure that I understand this. You are attaching the "work chain" to the center of the draped chain on the bucket by using the grab hook as a fixed connection?

Yes, that is what I was suggesting. Sorry for taking so long to reply.

 

[jodebg]

Thanks for the follow up.

And thanks to all who had some advice.

I'm going to use the 2 welded hooks. I think they will work great.

 

[GrandLakeGAR]

. I bolted a receiver to the center of my bucket. The base is 5" X 7" so the load is spread and I can use chains or a trailer ball mount.

 

[Gary Fowler]

Getting my B2650 work ready and have a question.

On my B7800 I have an anchor hook welded to the center of the bucket.

We do a lot of landscaping with sizeable stones and have used to center hook
for lifting and placing stones around our property. The weight in the center has bent
the top of the bucket.

The B2650 comes to us with a pair of grab hooks welded near the loader arms.

Not sure if I should buy weld one of Ken's anchor hooks in the center or use this set
up the way the original owner did. He used a 4' chain draped between the grab hooks
with a steel ring in the center for connecting to the chain doing the lifting.

Looking for some ideas as the best way to set this up.

I think you have already answered your question. I would never lift from a hook welded in the center. If I have a load that needs to be lifted from the center, I make a Y connection from the two lift cylinder location hooks and then hook on to the bottom of the Y with my load chain. If you have what you described, then that may work also. I would be a little concerned about the steel ring shifting off to one side if you are working on a slope or travelling across a slope with your load. With my Y connections, nothing can shift.

Edit: my apologies to those who already expressed my ideas and concerns with the steel ring shifting. I didn't read the whole thread before replying.

 

[jodebg]

Question regarding the horizontal chain running between the outside grab hooks. Going to cut a peice of chain to fit
and need to know the safer/better way to do this.

I'm thinking that a shorter chain (draped between the hooks) with a higher connection point (about 5" below the top of the bucket) may be better
than a longer chain where the work chain connects at a lower point?

 

[Henro]

Gary said:

"I would never lift from a hook welded in the center...



I have to wonder why not Gary? I can only imagine it's because you don't want to bend the top edge of your bucket. This is understandable if you don't reinforce it, or if it's not a heavy duty bucket.

I suppose with our smaller tractors it's not an issue, but lifting from the midpoint of a chain, which is held by grab hooks at the end of the bucket concerns me. That horizontal piece of chain will apply a tremendous side pull against the grab hooks when something is lifted from the center of it.

For me the center hook it's useful when I'm doing something like pulling out fence posts. If I'm carrying something I generally always use the side hooks. The center hook is also useful when pulling something. For example, I will often use my tractor to apply force to a tree (using a long series of chains) to make sure it falls in the right direction. I use the center hook for that.

If one does use the mid point of a chain stretched between hooks on his bucket, the more it is like a V shape the better. This reduces both the horizontal stress on the bucket hooks and the tension felt by the piece of chain between the hooks.

Aside from the risk of bending your bucket top (if you have a welded hook in the center, without adequate bucket top lip strength) I can't think of any reason not to have a hook in the center. I know I wouldn't be without one!

Bill

 

[MortOz]

I'm thinking that a shorter chain (draped between the hooks) with a higher connection point (about 5" below the top of the bucket) may be better
than a longer chain where the work chain connects at a lower point?

Hi John
Sorry, but I think your reasoning is wrong. To analyse this, you need to think of the tension in the chain (the force exerted), and the directions in which it is pulling. It is a vector problem from upper high school Physics - if you have a 10kg weight hanging from a single vertical chain, the tension in the chain will be 10kg (for the purists, I know forces are measured in newtons, the units don't matter here). If you put that same 10kg weight on two chains at an angle, then the total vertical force must still be 10kg, but you also have horizontal components added, so the tension in each angled chain is more than 10kg. The shorter the two chains, then the greater the horizontal components of the forces.
A quick demo - stretch a chain very tightly from the tow bar of a parked (brakes on) vehicle to a tree, and then stand on the chain - the vehicle will be pulled towards the tree, even though you normally would never be able be able to push it. The chain MUST move down to provide the upwards force supporting your weight, and the vehicle moves in just enough for the force vectors in the two halves of the chain to cancel your weight. Details at Pull a Car From a Ditch With the Super-Strength of Physics | WIRED

To get directly to the question of lifting loads with two chains, try: Vector Forces - ropebook
They have a number of excellent diagrams that would have saved me a lot of typing!

 

[John_Mc]

As others have already noted, the shorter the horizontal chain, the more stress you put in it, the hooks, and the welds. In fact, it's quite easy to put more than the rated working load (and even more than the breaking load) on that horizontal chain with even a moderate weight being lifted or pulled. For example: assume you are hooked to the midpoint of the horizontal chain, and that chain has a "sag" of 1/2 foot at the midpoint. If the hooks are 4 feet apart, the sideways force on each bucket hook will be 4 times the weight you are lifting (1/2 the distance between the hooks, divided by the "sag"). Tighten that horizontal chain up to a 4" sag, and the sideways force on a bucket hook will be 6 times the weight you are lifting.

 

[jodebg]

I was hoping there were some physics majors "on duty" yesterday. Good thing I did not cut the chain!

With the above information from John and Mort, is it safe to use this draped chain when lifting?

Appears that the connection point sould be close to the lower inside surface of the bucket?

Or, add a center hook?

 

[oldballs]

If I got the physics lesson correct..........just use a longer chain to decrease the angle of stress............but then, that might not work well based on the lift height of the bucket and object being lifted...........hum-m-m-