PTO driven stump grinder for small tractors

[Tornado]

Thanks for all the replies. I am aware of the various methods to burn out stumps. I may actually try the diesel method on one this weekend just for the heck of it. If all I had was a handful of stumps scattered around I would do these type of methods and not even consider a stump grinder. I would honestly prefer not to spend $2600 on a stump grinder. The only reason I am considering it now is because of the volume of stumps now on my place. There are dozens and dozens all over the place, and especially where I have now planted grass seed and expanded my yard, Its a real pain to mow the grass in these areas because of all the stumps I have to go around. There are just so many stumps everywhere now, and the hardwoods are always resprouting so I have to cut them or spray them , its just too many at this point. I may do an actual count on the stumps this weekend just to have a number, but Im talking over 60 stumps I know, with plans to add more. Its enough where I feel a stump grinder is finally making sense for me.

So do I and I have my own method. I cut them high (the bigger around the higher I cut them). Then I put a chain choker at the top and hook it to my drawbar and put the tractor in FWA 4 low and yank them out of the ground, roots and all. Let them lay there for a couple months do the dirt falls off, drag them to my burn pile and roast them. The big ones (over 15" in diameter, I have ground with a stump grinding outfit. Around here it's 50 cents an inch.

I wish I could take this approach. Unfortunately I dont have no where near enough muscle to pull most of these stumps up. Many of them are so stout that I think it would likely take a tract dozer or something to pull them. Many of these stumps are over 20 inches, many are live oaks. My little L2501 wont even budge them.

I am leaning pretty hard the last few days of placing an order for the WG24 in the very near future.

I do still have one question I am trying to find an answer to, and that is regarding the life of these teeth. I just have no experience with these teeth. Do they wear with just a couple dozen stumps, or is it more like it takes a large volume before they start to dull out? I really don't know what sort of lifespan I am working with. I'm talking just straight stump grinding, not hitting any rocks, etc. Is the life expectancy similar to a chainsaw chain for example? Or, is it more so something where you may never have to change a tooth for years? I need some kind of concept of how these teeth hold up.

 

[SidecarFlip]

The 'teeth' on every stump grinder I've eve seen (commercial ones) are Tungsten Carbide tipped (brazed on Inserts). Not sure about the Woodland Mills but, on most stump grinders built today the insert teeth are reversible, in other words, they have two cutting edges so when one edge gets rounded off or chips, they can be reversed.

They are quite expensive either way.

What happens is, the cutting edge gets rounded off from the abrasive effect of the dirt and pebbles and when they get rounded off, they no longer cut, they 'rub' and the power requirements increase substantially.

You can sharpen them but it takes a special diamond wheel and a precision grinder to holed the tooth dimension. I sharpen them for commercial stump grinders in the shop. You can resharpen them a couple times before the carbide insert gets too thin and fails.

That applies to commercial grinders, I have no idea what the Woodland Milles teeth even look like.

 

[Tornado]

The 'teeth' on every stump grinder I've eve seen (commercial ones) are Tungsten Carbide tipped (brazed on Inserts). Not sure about the Woodland Mills but, on most stump grinders built today the insert teeth are reversible, in other words, they have two cutting edges so when one edge gets rounded off or chips, they can be reversed.

They are quite expensive either way.

What happens is, the cutting edge gets rounded off from the abrasive effect of the dirt and pebbles and when they get rounded off, they no longer cut, they 'rub' and the power requirements increase substantially.

You can sharpen them but it takes a special diamond wheel and a precision grinder to holed the tooth dimension. I sharpen them for commercial stump grinders in the shop. You can resharpen them a couple times before the carbide insert gets too thin and fails.

That applies to commercial grinders, I have no idea what the Woodland Milles teeth even look like.

The teeth are listed as Carbide steel teeth, so likely the same as you are familiar with. They are $100 for a set of 6 teeth. The grinder takes 34 teeth in total.

I had already surmised how the teeth are likely to become dull over time, Im more curious on the time aspect. In other words - are stump grinder teeth something that typically sees fairly fast dulling,so they start to dull after just 20 stumps or so, or are they much more resilient and perhaps it takes over 100 stumps before you start to notice real wear. My issue obviously is I have no sense of scale on this and I am trying to grasp that scale. At $17 per tooth, I would hope these teeth are engineered to be fairly resilient, but I really have no idea. Stump grinding may be something that is really hard on the teeth, and it may be standard for them to dull out after 2 or 3 dozen stumps. I just have no idea.

 

[SidecarFlip]

Cannot answer that either. There are many different grades of Tungsten Carbide so tooth life entirely depends on the hardness of the material, how abrasive the soil is you are grinding in and the amount of stones encountered as well as how the inserts are brazed to the parent steel tooth itself. Tungsten Carbide is an extremely brittle material so the insert must be adequately supported or shock load will fracture the insert and make it unusable.

Most stump grinding machines (I'm familiar with Vermeer) are precisely adjustable for depth of cut just the keep the teeth out of the abrasive soil as much as possible. I have no idea about how the Woodland Mills or the Bauma grinders set their cutting depth. The trick is, if you will, to keep the teeth out of the dirt as much as possible.

Tooth life is a total crapshoot. In theory they could last for a hundred stumps or one stump, depending on the hardness of the carbide and how abrasive the surrounding soil is.

Unlike a chainsaw where you can resharpen the teeth, you cannot resharpen the the inserts without specialized equipment to hold the correct rake angle and it takes a diamond wheel to do it anyway (as in very expensive). I don't sharpen my chainsaw loops very often because I'm always careful about what I cut and where.

17 bucks a tooth isn't all that much in reality. Vermeer teeth are 60 bucks a tooth and most Vermeer grinders have 30 or more teeth (depending on the diameter of the wheel).

 

[SidecarFlip]

Your biggest issue will be, if you use the grinder on a low powered tractor and the teeth become dull (rounded off) the input power requirement will increase as the teeth become dull (rounded off) and a low power tractor won't develop enough power to drive a dull cutter through the stump and actually cut the wood. It might 'burn' it's way through however and that could be a very slow process (and stinky too).

Like a chainsaw with dull cutters.

Why I either roast my stumps or have one of the contractors I sharpen teeth for, grind them out for me. The smaller ones I roast, just easier and less hassle. I'll 'yank' them if they aren't too big, have the tractor to do that.

 

[B737]

Posts in the most recent WG24 thread about dirtydeed running through 75 stumps within a few days, and there are older threads with similar numbers.

 

[dirtydeed]

Tornado,

I don't think you will have much of a problem in your sandy soil. You can always "rotate" the teeth to different positions on the flywheel. The teeth that do the most work will be the outermost teeth (from center) and the ones that cut from the edge of the flywheel (these would be cutting the depth channel in the stump). I found that the teeth that are located closest to the flywheel shaft don't really do anything at all and therefor could be moved to the higher wear positions.

After grinding 78 stumps last month (all hardwood- ash, oak and maple), I'm planning on touching my teeth up this winter with a green silicon carbide grinding wheel. I've seen several youtube videos of folks using them to re-sharpen this style of grinder teeth.

In any event, I did find another supplier of teeth, at a reduced cost. They also do sharpening. If you look about halfway down the page, you'll see the listing for woodland mills.

Jeff’s Sharpening & Supply For All Your Stumpgrinder Sharpening & Retipping Needs

Regular Office Hours & Shipping Address9AM – 5PM EST M-F866-997-427712521 Warner StreetHudson, MI 49247 STAYING SHARP SAVES MONEY It’s what you need to be on a daily basis to keep …

www.jeffssharpening.com

Woodland Mills

Sharpening: $3.50
Retipping: $6.99
New Teeth: $10.99
New nuts: .50 each

Save up to $16 VS. OEM

 

[B737]

wow nice find steve!

 

[Tornado]

Thanks all for those last few replies that is very informative. That would suggest that I may could grind most all the stumps I currently have ( I estimate I have over 60 right now to grind) without having to replace teeth. This is kind of what I was trying to gauge. I think I will just purchase a set of 6 teeth with the grinder to have some backups. Perhaps if I do that, and then the ability to rotate some of the inner teeth to the outer part of the flywheel as mentioned by dirtydeed, I should be set for many years. The most stump grinding I will likely do on this unit will be right up front after purchase, from there I plan to have more stumps but it will come at 3 and 4 stumps here and there. Stumps that are out in the woods away from the yard or house I will likely not grind at all, just to save myself the wear. Its good to hear folks are doing over 70 stumps without touching the teeth. That gives me some indication of what I can expect. Dirty deed you mention wanting to touch up your teeth after 78 stumps so I assume you have started to notice some wear at this point.

Having never used a stump grinder, I was really in the dark on this particular issue. If I was going to be swapping teeth every couple dozen stumps for example then that was going to get expensive. Im glad to see its likely more like a chainsaw chain in that with good common sense use and keeping them out of the dirt as much as possible they can last quite a while.

 

[dirtydeed]

Yes, I did notice some decreased cutting efficiency towards the end of my job, but powered thru it. You'll get the hang of it after a few stumps...it just takes a little time. I would have to say that the worst part (for me anyway) was the pain that developed in my neck after a few stumps. It's rather difficult to get a good sightline on the work. I did find a way (position) that helped, but I won't even try to explain it in writing. It's just something that you will have to find for yourself.

Since we both have limited horsepower, I will point out that you really can't take to much of a cut on a single pass unless you are working on softwood or rotten stumps. I found that about 1/2" in depth worked best for me in my hardwoods. Be sure to cut all stumps as low as possible with your saw prior to grinding. It will save you considerable time and wear and tear on the grinder...at the expense of your saw chain and bar.

Anyway, I'm hoping that I don't come across as a woodland mills salesman, but I'm quite happy with the purchase. I had so many stumps to do that the thought of this undertaking was a bit overwhelming. I had thought it would take much longer than it actually did. I had only planned on doing the worst of the stumps initially, and tackle the rest over the course of a year. To my surprise, the grinder worked so well, I just kept going. Now, like you are planning to do, I will only have to deal with a few at a time as I cut more down. That'll be a piece of cake.

I had thought about renting a grinder, but most of what I found were pretty small machines and I didn't want to take a physical beating running one. I don't think I could've completed anywhere near the number of stumps I did with the rental machines near me. If I were to hire it out, they would've cost me a small fortune.

Best of luck to you in your decision.

 

[SidecarFlip]

No wonder I sharpen so many chipper knives and square anvils. I charge 50 cents an inch, he charges $1.40 an inch. Guess I need to raise my prices. Have a couple hundred knives in the shop right now.

far as dressing grinder teeth with a green wheel, all well and good until you screw up the rake angle, then they are toast and a green wheel is extremely slow as well. If you use one, wear a mask or you'll get silicosis.

 

[dirtydeed]

No wonder I sharpen so many chipper knives and square anvils. I charge 50 cents an inch, he charges $1.40 an inch. Guess I need to raise my prices. Have a couple hundred knives in the shop right now.

far as dressing grinder teeth with a green wheel, all well and good until you screw up the rake angle, then they are toast and a green wheel is extremely slow as well. If you use one, wear a mask or you'll get silicosis.

Good to know Flip...maybe we'll send you our teeth instead? I did see folks complaining that the green silicon carbide wheels are quite soft (as in they wear quickly) and create lots of green dust.

 

[Tornado]

If the teeth will do 70-100 stumps before needing to be addressed, I might would just buy new teeth rather than mess with sharpening personally. I suspect you would only need to replace the teeth see the most use, so just a handfull of teeth every couple years Id just get new ones. If I were planning to grind stumps all the time, or perhaps take on jobs doing it where Im using the grinder a lot more I think sharpening would make more economical sense. On my personal property I just wont have enough volume over a span of time to worry with the small amount gained from sharpening over buying new.

 

[SidecarFlip]

Unless the flywheel isn't concentric I don't see how one tooth (barring a fractured impact) would wear more than another. I know when I sharpen commercial grinder teeth they are all rounded pretty uniformly.

The 'green wheels' are mostly silicone with carbide mixed in and they are extremely soft and dusty. Diamond wheels are neither but are 20 times as expensive as a green wheel and you cannot do offhand grinding with them. Everything has to be jigged securely and the wheel mounted on a super precision spindle.

 

[NHSleddog]

Unless the flywheel isn't concentric I don't see how one tooth (barring a fractured impact) would wear more than another. I know when I sharpen commercial grinder teeth they are all rounded pretty uniformly.

The 'green wheels' are mostly silicone with carbide mixed in and they are extremely soft and dusty. Diamond wheels are neither but are 20 times as expensive as a green wheel and you cannot do offhand grinding with them. Everything has to be jigged securely and the wheel mounted on a super precision spindle.

You would need to look at the grinder to understand how the teeth on the outside of the wheel get MORE use than the others. More use = more wear.

 

[dirtydeed]

You would need to look at the grinder to understand how the teeth on the outside of the wheel get MORE use than the others. More use = more wear.

Correct, some of the teeth closest to the shaft center would be 3-4 or so inches above the bottom of the cut. No way I could ever have enough horsepower to grind 3 inches deep in one pass to engage those teeth. I'm sort of wondering why they even put them in there that far up the flywheel.

 

[dirtydeed]

Here's an example of that "other" method of stump removal...This one was a 16" maple that had partially uprooted in the wind and could not be ground using the stump grinder. It had to come out the hard way. All in, it was about a 4 hour job. Most of the time spent was filling the hole.

As I said before, using a backhoe for stump removal is less than ideal.

 

[Tornado]

Well folks, I just placed my order this morning, 10/19/2020. The product page is now saying "expected to ship in 5 weeks" so it seems they are getting more and more orders. Just 4 or 5 days ago that page said expected to ship in 4 weeks, and when I first looked hard at it about 2 weeks ago I'm all but certain it said 3 weeks. So, 5 weeks to ship, then probably another week or two to arrive way down here in Florida, I should have the grinder just before Christmas, I hope. I plan to post an in depth review with photos and everything once I get it.

I did a quick head count yesterday of how many stumps I need to grind right now. It was not an exhaustive count, just a quick walk around picking out the notable ones. I stopped counting at 75. If I went back into the woods just off my yard I could likely count enough to put me at or over 100 stumps total. I may skip grinding many of those in the wooded area because there is no real need to grind those and could avoid some wear by skipping. A large portion of my stumps will be big pine stumps. They are a soft wood, but I have heard some folks say that pine was one of the more problematic for them. I will review all of this once I have the unit.

To those who also recently ordered one, how is your order going? I notice it says my order is "being reviewed" and that I will get a separate email when it is processed. Any info on how long all that takes?

 

[B737]

They will call you the day after the order and review with you. Really good customer service. I’m scheduled for mid / early November

 

[Tornado]

They will call you the day after the order and review with you. Really good customer service. I’m scheduled for mid / early November

Interesting. I get so many spam and robo calls on my phone I dont answer numbers I dont recognize so I likely will miss the call. Hopefully they leave a message and I can call right back. Thanks for this heads up though.