Completely homemade excavator

[bindian]

Snowb,
Awesome project. Are the trailer wheels and tires gonna be your idler wheel at the tensioner? Also, can you show more photos and information on your Kubota crawler lift? That little thing looks awesome.
hugs, Brandi

 

[4570Man]

Machines with blades need to have the blade down, like a stabilizer, to dig effectively. That photo has the blade up. Also, the operator is not too well versed in what is considered abuse to a machine. All the machines weight is on the front rollers and fighting against the track tensioners.
As to the OP's machine, counter weight is a huge part of lifting. But so is experience. When your butt goes up, get closer to your work, or less material in your bucket. Also, you don't suppose to lift a heavy load with the boom and stick fully extended. Doing so just wears out the turntable bearings faster. Especially trying to swing with a load extended. You curl, lift and crowd the stick in and lift the bucket near the tracks, when you have a heavy load in the bucket, then you swing and then extend where you want to dump. Also, lots of machines have different lengths of sticks. The OP, after some trial and error, might want to make a shorter stick. It all boils down to experience and just what all the OP wants out of the machine.
hugs, Brandi

The blade was down. The stump wasn’t more than 5 feet off the blade and that’s about as close as that machine likes to work to itself. Usually when I feel the back end start to lift I stop but I pulled it up higher for the picture. Digging stumps is abusing the machine any way you go about it. Lifting the back end doesn’t hurt anything as long as you let it back down and don’t drop it.

 

[4570Man]

Going by this statement alone...........you are stating ALL long reach excavators are crazy.
hugs, Brandi

Those are for cleaning out ponds and they’re only on big machines.

 

[bindian]

Those are for cleaning out ponds and they’re only on big machines.

They have the same physics, no matter what size. The bucket has to be scaled to the stick and boom lengths. The machine will work, just more unstable in various attitudes. He is building a complex piece of machinery, which you call crazy. Anyone that can do all that at home, I tip my hat off to. I am sure the OP is experienced enough to not try to push the machine's envelope or do stunts to press a point.


Brandi

 

[bindian]

The blade was down. The stump wasn’t more than 5 feet off the blade and that’s about as close as that machine likes to work to itself. Usually when I feel the back end start to lift I stop but I pulled it up higher for the picture. Digging stumps is abusing the machine any way you go about it. Lifting the back end doesn’t hurt anything as long as you let it back down and don’t drop it.

The blade was down, and you raised your rear off of the ground, intentionally? Looks like abuse to me. How is digging stumps abusing the machine? They are made to dig and as long as you move outward on the roots, to a smaller section of the root if the bucket snags, where is the abuse? Experience (and paying $$$$ for your actions) negates any abuse and doing crazy stuff.
Brandi

 

[4570Man]

Digging stumps is about as hard as it can get for equipment. Maybe a D11 with a ripper would make easy work of it but it’s hard on small stuff. How does raising the rear off the ground hurt anything?

 

[bindian]

Digging stumps is about as hard as it can get for equipment. Maybe a D11 with a ripper would make easy work of it but it’s hard on small stuff. How does raising the rear off the ground hurt anything?

With the blade on the ground, Your boom, stick, and bucket hydraulics was fighting against your blade hydraulics. Blade linkages are stressed trying to keep your level while the boom, stick, and bucket was picking your butt up. Simple physcis. Do it enough and something will brake or blow.
Brandi

 

[4570Man]

Which is pretty much what it’s supposed to do. Is lifting the rear 1/4 inch vs 2 feet any different?

 

[snowb]

You can lever with the bucket a little bit but you still need to be able to lift and pull to get anything done and weight is your friend to do that. View attachment 673324

Referring to the approximate dimensions of a 9 ton excavator like this one, depending on the angle of the arms shown in the photo, the bucket is about 10 feet from the excavator.
By calculating the maximum possible force limited by the weight of the excavator, if we pull on the stump at the same time as we try to lift it, the force will be 6900lbs before the rear of the excavator lifts ( this is clearly the case here, it does not represent the limit of the excavator) In addition to exerting less force on the stump a good part of this force is wasted by pushing the stump into the ground towards the excavator.
By performing a straight upward movement only upward (approach the big boom and move the betit boom back slightly so that the bucket remains in the same horizontal position, the maximum force before the rear rises would be 11900lbs !!! in the latter case the action will be much more efficient and the excavator will give its full potential in hydraulic power without the rear lifting. This is simple math.

 

[snowb]

This excavator is only 2400lbs and has a reach of approximately 12 feet from the front axles. There is still a way to work without overturning, even if it is not the heaviest in relation to its reach, in addition the ground is super soft there, it only holds by the grass.