lift capacity vs. breakout force

[Eagleview]

No mate , it's 8.00am Friday morning . This is the best time to have a yarn . You guy's are finished for the day and i'm just starting .

 

[IslandTractor]

No mate , it's 8.00am Friday morning . This is the best time to have a yarn . You guy's are finished for the day and i'm just starting .

I was way off. I thought there was about a 11-12 hour time difference to the US East Coast. Have a good day.

 

[IslandTractor]

No mate , it's 8.00am Friday morning . This is the best time to have a yarn . You guy's are finished for the day and i'm just starting .

I was way off. I thought there was about a 11-12 hour time difference to the US East Coast. Have a good day mate.

 

[Eagleview]

My mobile phone tells me it is now 8.19PM in New York and it is 11.19AM here in NSW Australia .

 

[Farmerford]

Iron Horse:

Nice machine. What is the lift capacity of your excavator with he stick pulled bacK to vertical? Do you dig around the trees first, or do you just pull them out without digging?

 

[Eagleview]

No digging of trees this size . It would be too time consuming to keep removing the grab and fit a ripper or bucket . It has a lift capacity of 11,000 kilograms (about 12 tons) but does not rely on this function when extracting . It is a combination of all functions to pluck a tree out . Mostly i pull the dipper arm in while rolling the grab back . This tilts the tree towards me and breaks the roots . I keep on pulling with the arm which drags the tree through the soil 8" or so (the top ram pushing on the short arm extension does this) , then i lift which pulls it out of the hole . I bang it up and down a few times to get the soil off of the roots and back into the hole . I then use the root system like a big paint brush to smudge the soil and grass surrounding the hole which covers it over . 3 weeks later the grass has grown back and you cannot see where the tree was .

On edit .
The tree in the picture was a little stubourn , i had to grab it a bit higher for leverage and push it away first to loosen before doing the above proceedure . Also this particular tree had a branch that looked like it would break off if i banged it up and down and land on my cab so i did'nt , that is the reason there is soil still on the root ball .

I did'nt know i could click on the photo to enlarge it , i just did and i can nearly read my phone number on the boom .

 

[Window Geek]

I believe that they build or order a certain bucket, and then figure the cylinder size that will give a reasonable breakout before the bucket is destroyed. (SNIP) A shorter bucket on the same frame, will have a greater break out force, due to mechanical advantage. The same thing applies to the lift cylinders also. You could go to a larger cylinder, but you might place your front axles at risk, by overload. Just enough is what they settle on.

You're right there, JJ. The breakout is usually higher than lift capacity. You can use that to your "advantage" for lifting things heavier than your lift capacity. When trying to unload my log splitter and PHD off the pickup truck at the same time, I learned that Kubota folks knew about guys like me and set the pressure relief to keep me from bending the loader.
BUT, with the breakout force at about 850 pounds, I was able to curl back on the bucket just enough to get the crates off the pickup and drive the truck out from underneath. Cool! This was during the first few days of owning my slightly used machine. (I bought it with less than 50 hours on it.)

Later when I tried to do a little grading, the left-hand edge of the bucket seemed to hit the driveway about a half inch before the right-hand edge.
I'm sure the first owner must have bent it!

We've all seen that bucket edge flex with fork attachments or picking up that slightly too big rock in the back yard. It's the breakout of the bucket, with its shorter, stronger mechanical advantage, that lets you get it off the ground. You can move it, but you'll never pick it up.

 

[Eagleview]

You're right there, JJ. Later when I tried to do a little grading, the left-hand edge of the bucket seemed to hit the driveway about a half inch before the right-hand edge.
I'm sure the first owner must have bent it!

Do the oposite to what you did to twist it . I'm allways twisting my loader , hitting unseen stumps etc . I just put the other corner against a stump , select low low and give it a push , sometimes while lifting . It will go back , it's not bent , only twisted .

 

[fitterski]

This may seem like a dumb question, but ....

There is no such thing, only answers can be stupid and Picasso discovered that much in spite of his handicaps when he said "Computers are useless, they only give us answers"

So I feel at ease jumping in here albeit a little late. My Cat-426 has a breakout force of around 6000 lbs against a max lift of maybe 4000. I always presumed that maximum lift was load lifting capacity before the rear goes airbone, and that breakout force was total bucket upward force limit that can be exploited when the bucket is higher and nosing over becomes mostly impossible. One ezample of this is when forcing with the bucket at a high angle against a wall of cooked stone (once blew a front tire doing this). I just can't see that single tilt cylinder pumping more than the dual bucket lift cylinders, superior geometry and all. Correct me if I'm wrong, it wouldn't be the first time.

I now have a more or less 12000-16000 lb 5 foot high retaining wall to lift 3 inches, the amount it has settled toeing-under in more than 20 years. The 50 ton chinese jack I bought isn't doing it because it's pushing the 16x16 inch square plate under it into the ground instead. This may improve as I ram more material under the plate but it may also prove to be limiting in the end.

So how does this tie into the topic? I plan to maybe borrow a big loader to try it with, I can get to the wall from above with the bucket lip easily right over the lift point approaching it on the high refill side of the wall. I'm thinking 2 chains with L shaped clips made from 1 inch plate. My 426's breakout of 6000 lbs is sure to be inadequate (from experience) but I'm curious as to what a bigger loader might be capable of.

 

[dadohead]

The breakout force is the amount the bucket can exert in it's crowd back function ie. tearing out a tree root while rolling the bucket back , as opposed to trying to lift it with the loaders lift arms (lift capacity).

Dead on... The bucket force is designed to overcome the crowd which can in-turn overpower the boom. That way the operator always has one more trick in his bag and doesn't get the bucket stuck.