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EWY'S Tree Service

New Member
Joined
Dec 19, 2020
Messages
4
Location
Philomath, OR
Hello,

Has anyone ever added a cylinder to their compact excavator to give it better lifting capacity?

I own a tree service in Oregon and am looking at buying a piece of equipment for moving and loading logs with. Shovel loaders used in forestry have a knuckle style boom where the stick cylinder is below the joint, giving it better lifting strength.

shovelloader.jpg


Excavators have their cylinder mounted on top to give it better digging strength:

compactexcavators_models_kxseries.png


Unfortunately, I haven't found anyone who manufactures a compact shovel loader, so a compact excavator is my next best option. Has anyone ever added a cylinder on the underside of a compact excavator boom to give it better lifting power? Would this even be feasible? What problems do you think may arise?

Thank you very much!

For context: I'm looking at getting at 10k machine.
 

Welder Dave

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Oct 11, 2014
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12,548
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I think lift and tipping capacity would be a bigger concern than where the cylinder was mounted. Look in the forestry forum on here. One of the members designed and built his own special purpose forestry machine from various other machines.
 

treemuncher

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Dec 31, 2006
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751
Location
West TN
Occupation
eatin' trees, poopin' chips
With a 10k lb machine, you will be handling matchsticks, not logs, due to the weight of the machine. I've done enough clearing work lifting logs with my PC200 to know that I would need a much larger machine to handle full size logs, all day long, if I wanted to be in the log recovery business. A fresh cut pine or oak can easily have logs in excess of 5k lbs, depending on the length and diameter of the wood of course.

Now if you are handling balsa wood or royal paulownia, you could get away with a slightly smaller machine because that wood is less dense than most any other. I just rented a 12.5k lb machine for some septic work - it did not have enough ass in it to handle small stumps let alone logs. You should consider nothing less than a 12 ton class machine, in my opinion, for handling wood if it is larger than brush. Just my opinion.
 

uffex

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Lincoln UK
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Good day
The configuration you refer has the term materials handling as you use the positive side of the arm cylinder it would certainly remove any limitations you may have with casting the timber away from the machine, the stability would remain much the same.
Kind regards
Uffex
 

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John C.

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Logging shovels use that configuration for lifting height and reach. I used to see 20 ton machines with quick couplers and heel rack and grapples. The set ups worked but the big problem again was reach and height. There were companies that added another boom cylinder boss to the bottom of the boom to increase the lifting height. Those machines used the bucket cylinder to operate the heel rack and the thumb circuit to operate the grapple open and close. The had to add a circuit to operate the grapple rotate. Most used an EELAC valve but some machines had the capability of adding an extra pump and valve.
 

EWY'S Tree Service

New Member
Joined
Dec 19, 2020
Messages
4
Location
Philomath, OR
With a 10k lb machine, you will be handling matchsticks, not logs, due to the weight of the machine. I've done enough clearing work lifting logs with my PC200 to know that I would need a much larger machine to handle full size logs, all day long, if I wanted to be in the log recovery business. A fresh cut pine or oak can easily have logs in excess of 5k lbs, depending on the length and diameter of the wood of course.

Now if you are handling balsa wood or royal paulownia, you could get away with a slightly smaller machine because that wood is less dense than most any other. I just rented a 12.5k lb machine for some septic work - it did not have enough ass in it to handle small stumps let alone logs. You should consider nothing less than a 12 ton class machine, in my opinion, for handling wood if it is larger than brush. Just my opinion.

Hi Treemuncher,

Thanks for your reply. I have been renting a lot lately. A 10k has been about the optimum machine for me so far. It can handle much bigger sticks than the 8k and is at the upper threshold of my towing capabilities. I'm not looking at moving a bunch of 42' logs with it. The intent behind the added cylinder is to give better lifting capacity without the added 2000lbs of a 12k machine.
 

EWY'S Tree Service

New Member
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Dec 19, 2020
Messages
4
Location
Philomath, OR


Hi Tags,

That is an awesome setup! I certainly don't have that kind of budget of time though. It is good to see thought that their are some smaller machines with the "materials handling" cylinder configuration. Thanks!

I want to maintain the digging strength of a regular excavator setup (for digging out stumps) while also boosting the lifting strength.
 

skyking1

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Nov 3, 2020
Messages
7,676
Location
washington
The top mount stick cylinder is also for clearance when digging deep and in trench boxes and such. A bottom cylinder is going to get in the way of conventional trenching, and may also hinder the stumping a bit. I think it is workable though.
I did some tree work with our new 35G mini, and was impressed with the logs it could handle. I could load 12' Doug fir logs 20" diameter over the side of the dump truck. It moved some big cottonwood logs, certainly big by mini standards.
I can see how a 10K rig would be handy. Only 79" wide in the John Deere line, it would get into some tight spots.
 

Tugger2

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Mar 22, 2018
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British Columbia
I have a 303.5 Cat . Its amazing what it will do ,digging stumps moving logs ect. Sounds like your business needs a smaller machine for access reasons and it works with what you can haul so it keeps you flexible . A bigger machine wont go where you need to go . If you use it carefully you can push its limits and get a lot of work done, just be sure to charge accordingly so you can fix that sudden failure that comes from pushing your equipment for the customers benefit. I wouldnt get carried away with modifications like undermounted cylinders ,theres too many other considerations for what you will gain. Unless you put something together like Coastal did ,i think you would just spend money devalueing your machine.
 

673moto

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Maybe a smaller machine (35-50ish) could be modified with larger cylinders and valves/pressure?
Idk how that stuff works... but you must be able to push the limits of what these little machines do?
 

skyking1

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washington
They're well balanced they already have enough hydraulic forces for the amount of weight they can handle. I think he's looking for a change in geometry to get more up higher.
 

lantraxco

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Jan 1, 2009
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Elsewhen
Try just using a dangle head grapple on there, with a bit of practice you can do a hell of a lot with a small machine.

Otherwise yeah you could add a similar sized cylinder underneath to assist the one on top, tee into the lines, even make it removable if it got in the way digging. Suggest you reinforce the hell outta the stick, and some on the boom, you're working somewhat backwards to the design goals for an excavator.
 
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