Stump Grinder Build

hddnis · Jul 28, 2014

Greenteeth.com - Why Grind When You Can Cut?

Mr. HE

Arc weld · Jul 28, 2014

Just saw this thread. One thing I noticed was that the motor wasn't rated for 3000 PSI continuous. It was 26xx something. Can you adjust the pressure so you don't destroy the motor in a short time? Also would be good to put a guard over the top of the cutting wheel. Maybe you could attach an adjustable mirror to a post on the frame to make it easier to see what is happening?

Baby Grand · Jul 28, 2014

Looking good! Seems to just munch away at a comfortable pace.
Seeing this makes me want to try building one for myself.

woodlandfarms · Jul 30, 2014

Stump grinder complete

I welded up a cover for the top of the machine. It reduces the flying debris. A flap on the front would also be an idea, but I am worried about sucking it in and as the machine works sideways, I think I am going to just let it go.

I also cut the shaft off.

So far I have half a dozen stumps gone. Smallest is around 12". Last night I took out two of my 30" stumps. Man did that turn into an ordeal. I also took on a 40" rotted redwood. Really, it disapeared in a cloud of dust in about 30 seconds.

k0ua · Jul 30, 2014

It looks to me like you are doing pretty good with it. It turned out well.:thumbsup:

Renze · Jul 31, 2014

hddnis said:
Greenteeth.com - Why Grind When You Can Cut?

You just showed the style of cutting wheel i was looking for, to build my own... Apparently the smoothness of cut has nothing to do with the number of teeth so i'll make a quadwheel:
Green Manufacturing - The Quadwheel

having a wheel plasma cut, together with four claws, is cheaper than using lots and lots of chisels and holders and pockets on a wheel that needs machining..

woodlandfarms · Jul 31, 2014

That quad wheel is very impressive. Just didn't feel it in my design... Too many variables and as I had to have the wheel made costly.

In my first post is a wheel design provided by green teeth.

grainger12002 · Jul 31, 2014

Nice Job Woodland, Keep us posted on its durability and how the engine handles the rpms's, oh, keep the pics coming too !!!!!

From CT

woodlandfarms · Jul 31, 2014

If there are pix of things you want a closer look at, please let me know.

I really have not been kind to it on the past few stumps. stalling, jamming, just seeing what it will take. Motivation on this is in case a friend decides to use it (which will probably be never as I am not comfortable with that).

In terms of failure, things on my mind are in order of failure

The Motor - In hindsight I should have gone deeper in the wallet. My motivation was to build a stump grinder for under 1K. So the motor I got was what I could afford. Not the best plan. It is working, and working well, but in the end I won't be too surprised if it gives up the ghost.

The Wheel to Shaft mount - This is something I found on ebay. When I look at other designs, the mounting ring is a custom item. I am essentially buying heavy duty pully connector.

The Pillowblock Bearings - The design itself is correct, but I found out these are chinese made. I have heard really mixed results on chinese bearing so this could be my third failure area.

But, basically I grind a stump, pull back, and inspect. And serious inspection. Looking for cracks and looseness.

Zick · Jul 31, 2014

Nice work!

If your still having problems seeing the wheel from the driver seat, what about mounting a camera on the grinder frame and get a small LCD display.
Just a small backup camera would work great here.

PapaPerk · Jul 31, 2014

woodlandfarms said:
If there are pix of things you want a closer look at, please let me know. I really have not been kind to it on the past few stumps. stalling, jamming, just seeing what it will take. Motivation on this is in case a friend decides to use it (which will probably be never as I am not comfortable with that). In terms of failure, things on my mind are in order of failure The Motor - In hindsight I should have gone deeper in the wallet. My motivation was to build a stump grinder for under 1K. So the motor I got was what I could afford. Not the best plan. It is working, and working well, but in the end I won't be too surprised if it gives up the ghost. The Wheel to Shaft mount - This is something I found on ebay. When I look at other designs, the mounting ring is a custom item. I am essentially buying heavy duty pully connector. The Pillowblock Bearings - The design itself is correct, but I found out these are chinese made. I have heard really mixed results on chinese bearing so this could be my third failure area. But, basically I grind a stump, pull back, and inspect. And serious inspection. Looking for cracks and looseness.

Don't knock it. It's working! Run it till it starts to break then improve. That's the engineering way! (0:

J_J · Aug 1, 2014

woodlandfarms said:
If there are pix of things you want a closer look at, please let me know.

I really have not been kind to it on the past few stumps. stalling, jamming, just seeing what it will take. Motivation on this is in case a friend decides to use it (which will probably be never as I am not comfortable with that).

In terms of failure, things on my mind are in order of failure

The Motor - In hindsight I should have gone deeper in the wallet. My motivation was to build a stump grinder for under 1K. So the motor I got was what I could afford. Not the best plan. It is working, and working well, but in the end I won't be too surprised if it gives up the ghost.

The Wheel to Shaft mount - This is something I found on ebay. When I look at other designs, the mounting ring is a custom item. I am essentially buying heavy duty pully connector.

The Pillowblock Bearings - The design itself is correct, but I found out these are chinese made. I have heard really mixed results on chinese bearing so this could be my third failure area.

But, basically I grind a stump, pull back, and inspect. And serious inspection. Looking for cracks and looseness.

Can you perhaps grind into a tough hardwood stump and and post a video?

Am I correct that you can rotate each tooth 4 times before you have to resharpen.

woodlandfarms · Aug 1, 2014

3 times total. Triangle shaped base. Outside of my walnut that I already took out the only other thing I have is maple. Will that work? Alder is the stumps I take out the most. Pretty soft I think.

Renze · Aug 3, 2014

woodlandfarms said:
That quad wheel is very impressive. Just didn't feel it in my design... Too many variables and as I had to have the wheel made costly.

The actual greenwheel is indeed costly because it is machined, but i would just have it plasma cut. And maybe some mating surfaces dressed on a mill at my shop-neighbours work. (there are about 4 hobbyists that have a workshop in an old chicken barn where i live)

The quad wheel being fully machined is a way to create added value to market it as a premium product (and a premium price while it costs less to produce than a disk with a couple dozen of bits) but i dont see any real benefits in getting a closer tolerance than the half millimeter on plasma cutting... I mean, the deviation of a plasma cutter is pretty constant, so if it takes a wee bit more off than the CAD file on one side, it will do the same on the other side so the balance will be good no matter how close the actual work meets the CAD file, as long as its cut with the same torch setting.

A disk with multiple holes for bits or chisels also needs either to be made on a CNC mill, or it requires the laser/plasma cutter to mark all hole positions to get the right balance, as most cutters cant cut holes with a diameter smaller than the thickness of the steel without making a mess.

I think im going to make a simplified quadwheel... I ran more than a day or two in manufacuring plants, in the office as well as on the floor so i see some opportunities to cut costs on this....

woodlandfarms · Aug 3, 2014

Can't wait to see it. No true machinists in my friends list.

woodlandfarms · May 24, 2015

Bumping this back up, wanted to share some mods in case anyone is going to copy the plan.

Primarily the mods center around the use of the stump grinder as a trencher. We laid over 1800 ft of irrigation line and used the stump grinder as a trencher.

First realization was that the clay quality of our dirt clogged up the sealed version of the blade protective cover. So, I made this open air version. What you cannot see is the angle iron down the center that pushed the dirt off to the side.

Let me say this is a work in progress.... The inboard side dumps fine, the outboard side still sends tons of dirt everywhere. I am going to work on this item some more

The second mod was a skid. The motor is mounted with c channel. when the grinder is all the way in the ground and pushing forward you get a nasty gouge in the ground (outside of the trench). So I pulled out some 1/2" scrap flatstock and bent it into a mini ski. Just remember you do not want it longer than your grinding wheel cause it will mess you up when you are stump grinding.

The final item was an aha moment. The attachment sits funny on the ground when you are trying to pick it up. I could honestly spend 2 or 3 minutes trying to grab the darn thing, getting off the tractor, moving it around. The neighbor suggested I build a cart. and that was the direction I was headed in, when I was looking at my trailer and realized I could probably rig up something attached to the grinder itself.

So a couple of HF hitch sleeves, a bit of 2" square and a couple of feet made of scrap and a few holes.

Pictures display standing and what happens when attached to the tractor.

woodlandfarms · May 7, 2016

Another update, after 2 years and over 100 stumps (probably way way more) my grinders is working well. No parts failures, outside of a broken tooth when I found a metal culvert that I had no idea existed. Teeth were rotated ove the holiday... But when a neighbor looked at them he said I rotated too soon.. oh well.