Stump Grinder Questions!

[Highbeam]

So why not buy a stump jumper from a brushhog that will fit your gear box and then weld the disc to that? Can the typical gearbox be run sideways without cooking the bearings?

Why not just use a brush hog and replace the blades/stumpjumper with your disc/teeth? I suppose grinding horizontally wouldn't allow you to go very far below grade.

 

[tractordriver]

YouTube - John Deere 8100 and Rotor S stump grinder
this is neat but don't know if its diy.

 

[sandman2234]

YouTube - John Deere 8100 and Rotor S stump grinder
this is neat but don't know if its diy.

That machine is definitely not diy on a homeowners point of view. I also wonder if it is a feasible design for most of us, since it is being powered by a 160 horsepower machine. I wonder what the minimum horsepower it would take to operate it. In another video by the same company, they show it cutting a row of what appears to be planted pines, or maybe Christmas tree stumps, and the operator goes from one to the next just like clockwork. He hits each stump right in the center, without having to allow for slop in the 3pt, etc. It makes me wonder just how many of these stumps he has done in the past. (Or is the video edited to make the machine appear easier and faster than it may be.) I know it is larger than I want to put on my 70hp JD. Notice the way that huge tractor shakes when the auger finds something it doesn't like!!!

YouTube - Stump cutter

I saw a stump grinder made from what appeared to be the design of a bush hog/ tree cutter at the auction I went to in Ok (Brinkley Auction). It used carbide cutters on the bottom of a flat plate mounted on a right angle gearbox. I don't think it would go much below grade, but it would get them low enough to mow over!
David

David from jax

 

[sandman2234]

I also am of the opinion that using a backhoe knuckle probably wouldn't be the best idea. One of my problems is keeping the slack out of the stumpgrinder, and by adding a backhoe to the mix, you have just added several more places in which the slack shows up. Simple seems to work better than complex when trying to keep a spinning disc in line.
David from jax

 

[Scotty370]

Doggone guys! That's one serious rotary devise! My 4100 JD would be spinning around the drill bit as soon as it engaged the stump!! I'll stick to my original design, which is just about complete. I bought some steel yesterday and would like to get started, but it's only 9 degrees out, and I don't use a cutting torch inside the shop!!! Guess I'll finish drawing inside the house. Funny how the wife doesn't seem to share my excitement about a project comming together, when it involves steel plates and parts on the living room carpet. Off topic a bit: Do any of you DIY'ers find a project a legitimate reason to purchase,(read-'dream') about purchasing equipment that would really help, and be 'cool' to own? Man I'd like a plasma cutter!! Oh well, back to reality! Highbeam brings up a point that I hadn't considered about the gearbox orientation. I got to believe it will be OK, since if anything, the input gear will be 'laying lower' into the gear oil than when it's in it's upright position. only down side would be if there's a vent hole in the box! I'd have to plug it and redrill one facing skyward! Thanx again folks! ~Scotty

 

[Renze]

YouTube - John Deere 8100 and Rotor S stump grinder
this is neat but don't know if its diy.

This thing will cause more wear and tear to the average small farm tractor, than to dig and pull the stumps out... The latter would probably be more statisfying too...

 

[sandman2234]

On a gearbox vent, instead of redrilling a new position (which adds chips to the mix, and having to disasemble to correct that) how about just adding an elbow and a short pipe extension to establish the correct direction? A brace to hold it in place might also be a good idea so it doesn't get knocked out of position and you loose all of your oil. A brace/bracket might also protect it from getting knocked off in close quarters.
David from jax

 

[Scotty370]

Good point on the vent re-route. I don't even know if it's vented, but figure it must be so the seals don't blow out. Back to the MetalSupermarket Monday. The drawings are done, and those guys are great shearing parts and pieces. I know, I'll get some flack from the guys that 'cobble' stuff together from junk-yard finds, and are pretty ingenious at doing so. But, I really don't need all that much, and it's sure nice dealing with clean stock. Especially since most of our JY's are snow covered, or mud pits. ~Scotty

Oops! Just thought, if the existing vent ends up below the oil level, your idea may not work. The expansion would force oil up the re-route line.

 

[MJPetersen]

Oops! Just thought, if the existing vent ends up below the oil level, your idea may not work. The expansion would force oil up the re-route line.

However, if that is the case, then you maybe able to reverse the level check and vent plugs. The old level check becomes the vent, maybe with some extension. And the old vent can become the level check with a proper pipe extension.

I know that we are just guessing before you have actually analyzed exactly what will be.

Mike

 

[sandman2234]

Turn the gearbox by one set of mounting bolts either clockwise, or counter clockwise, to move the vent above the oil level. Mounting bolt holes are usually evenly spaced, and the gearbox doesn't know you turned it,lol.

David from jax