Anybody built a stump grinder?

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I've got a few stumps to grind and after looking at the smaller hand operated grinders I kinda want to build one.  It appears that there is really only two important parts.  The engine and the cutting wheel.  For the engine I would prolly by a 13hp honda clone for $300-400.  For the cutting wheel I was thinking a 10"-12" x 1/2" or 3/4" thick piece of steel with lathe tooling welded to it.  I have worked on landscaping trenchers before that used lathe tooling for teeth. I know this for a fact as I was the one welding on the replacements.   They needed replacing a few times a season after digging dirt and rock.  Shouldn't have a problem with wood.  I figure if I bolted the wheel to a hub, then I could have a few spare wheels ready to go as the cutters got dull (did this with the trencher).Sure, I could rent one, but where's the fun in that?  Plus I know of several people needing stumps ground and I could prolly make some money, or at least break even and have a tool to show for it.  I could just buy one, but they cost $2-4k and the video's I've seen aren't very encouraging.This is the type I am thinking of.......any thoughts? Attached ImagesMy name's not Jim....
Reply:Only three points:  1).     They needed replacing a few times a season after digging dirt and rock. Shouldn't have a problem with wood.
Reply:Seen lot's of corn and beans, don't recall any wheat.Yes, I know the stumps are in the ground.  The trenchers I worked on were being used to cut trenches for brick edging in a housing developement my former boss owned.  So a season's worth of use was actually quite a bit of smacking dirt and rock.  I think they should last a lot longer dealing with mostly wood.I paint everything, sometimes even before testing if I am confident in my design.My name's not Jim....
Reply:Boost I replaced a ton of teeth on stump grinders by vermeer.  They had a removable pocket that was a lot easier to replace teeth on by simply removing 2 bolts and selecting whether it was a left, right, or straight tooth.  The smaller cutters are a real handfull to hold steady in the cut and throw a lot of the chips back on the operator.  Several manufacturers are making small units that will travel through a standard gate too, but stability is an issue with them.  I have seen the smaller ones powered by Kohler 18 hp lawn and garden engines, while the larger vermeers were powered my the 65 HP Wisconson V4-65D's.  Mass in the flywheel, and arm assembly as well as spaxe between the wheels is a big part of how good they work and how stable they are in the cut, so bigger is always better.   Take a look at vermeer and see the difference.  Hope this helps.BobI'm spending my Kids inheritance, I dont like him that much anyway!!!!!!Enuff tools to do the job, enough sense to use em.Anybody got a spare set of kidneys?  Trade?
Reply:Bob, I have looked at that type of cutter set up.  It is nice, but beyond my machining abilities right now.  I want to keep things simple as far as the cutting wheel goes.  For the running gear I have a couple of hub assemblies and 13" car tires to fit.  I was thinking of locking both tires and swinging the whole cutting head, engine and all on a pivot rather than locking one tire and using it as a pivot point.  I've been watching more video's and it appears the the operator has a lot to do with how well a smaller grinder works. Are you surprised?  I'm not.My name's not Jim....
Reply:Boost if I remember correctly the wheels were actually really cheap and the cutters were like 1.65 each.  The problem we had was the operators would not grease em during the day and the bearings on the pillow blocks stuck down in the ground caught a fit.  Once I got a couple of good operators we cut down that expense a ton.  Some of the current designs are using hydraulic motors to turn the wheel and cylinders to swing it in the cut and were pretty simple to work on and get cheap parts for.  Rayco and vermeer are pretty much the best 2 builders and worth copying as much as possible.  I think you vould get away pretty cheap and make a buck or three if you do it right.  Good luck and since i worked on a ton of em if you need any help let me know and I can get some parts drawings and parts lists together if you need em.  Dont forget to post up the pics of what you end up doing.BobI'm spending my Kids inheritance, I dont like him that much anyway!!!!!!Enuff tools to do the job, enough sense to use em.Anybody got a spare set of kidneys?  Trade?
Reply:What size stumps are you planning on grinding out, and how deep do you want to grind them?I have used the type of grinder in your picture, as well as a larger hydraulic operated one, and for doing anything over a 12" stump and wanting to grind down more than a few inches I would only use the hydraulic one.My dislikes for the one you reference in your picture are as follows (so if you design one like this you may want to design around this):1.) The head of the unit does not have enough weight and you really have to man-handle it to get it to grind down a larger stump.2.) Locking 1 wheel sucks, and it always slips in dry dirt and the head gets out of poistion to make nice crescent shaped passes over the stump,3.) It gets increasingly more difficult to use this machine the deeper you have to go.Positives for this unit:Its narrower so it can fit into back yards through narrower gatesThings I like about the hydraulic model:1) Its fast. With the larger motor and bigger cutting wheel it goes through large stumps quickly (15"+)2)You drive it up lock both wheels and then the entire head swivels. You make side to side passes with a lever, then drop the head down in small increments with another lever and the weight on the head is enough that the machine rarely kicks up at all.3) Once you get it where you want it, there is little grunt work to do... push some levers and move forward and back and you are done.4) These units can go deeper much easier making removing larger pine stumps etc a lot easier.  Its pretty simple to grind down a foot, which is not the case with the other models.At least around here the one like you pictured rents for 100 bucks for 3 hours, and the hydraulic one goes for 160 for 3 hours.  If you get them on a friday afternoon you keep it till monday at 8am for the same price.I understand wanting to build one and having it be handy to have around, but after experiencing using one a few times if i ever had larger stumps to grind I would rent a hydraulic one simply because at the end of the day with the manual one you are about as beat up as the stump you removed.
Reply:ggarner,    Hydraulics is definately out due to cost.  I would consider maybe a 12v actuator for the swing though.  I understand the weight of the cutter wheel thing (flywheel effect) I plan on going heavy as I can muster up.  I have a 1-1/2" plate here if need be.  I do plan to lock both wheels and swivel the head, manually though no hydraulics.  I only need to grind these things low enough for grass, maybe 6"? The stumps I currently have in mind are 2 ash about 18" in diameter (mine), 1 apple about 16" in diameter (mine), and 6 pine stumps about 12"-14" in diameter (neighbor at my other place 3hrs away).  I'll try to get a simple sketch together soon.  Any thoughts on the drive?  I'm thinking just doing chain drive and using a go-kart clutch to give it some give if it bites in.  That's the easiest/cheapest solution I've got so far.  I don't like shear pins.My name's not Jim....
Reply:Here's one made by Rayco similiar to what you are talking about,it has a 13 hp motor on it Attached ImagesLast edited by dugndeep; 08-29-2010 at 04:41 PM.Reason: moreMaxus Pro-125 MigChicago Electric 90 amp DC flux-coreLincoln Electric AC 225 tombstoneO/A torchM/O mini-torch10 acres of flatland15 acres of holler
Reply:Maybe it would be safer to have it be belt driven, that way if it hits something really hard the belt would slip rather than having a chain absorb all of the sudden impact?  I dunno... just a thought.I like your idea of the swivel head while the wheels etc stay stationary, should allow for it to be much easier to use.  Maybe you could even put foot rests on the frame and once it was in position you could stand on the frame to swivel it and raise and lower the head?  Not sure if this would make is significantly more dangerous though.
Reply:As an arborist I've been around a few stump grinders.  Those small grinders suck, sorry.  If your doing 6" diameter stumps, sure.  It takes a lot of horse power to rip a stump.  Just trying to save you the time, money, and heart ache.FWIW.  I bought a Vermeer 252 self propelled stump grinder for 2k.  I used it a bit, but have a sub with a big grinder who does them on the cheap.  It wasn't worth me even having my own grinder.  In the end I sold it for 4500, so I made out. Deals are out there, I've seen those little turds on craigslist going for 600.
Reply:Boost,  tooth holders may be available as a weld on part.. Might be worth checking out.Neat idea though, If you can make it pay for itself, it will definitely be a winner.
Reply:Originally Posted by brendonvAs an arborist I've been around a few stump grinders.  Those small grinders suck, sorry.  If your doing 6" diameter stumps, sure.  It takes a lot of horse power to rip a stump.  Just trying to save you the time, money, and heart ache.
Reply:This sounds like a very usefull project and I will be watching to see how it turns out, might have to look into this for myself.Did some googling and here is a link to the operator manual and parts diagrams, in case you haven't looked at them yet.  http://www.uspraxis.com/video/9-13hp-manual.pdfThe drive is by a 3V belt.  Looks to be fairly simple in design.  If this was me I would check into how much the teeth cost and might just buy them.  They have a nice design, just mount them in between two plates of steel.  There are some nice color pics of the cutting wheel and pillow blocks in the operators manual.
Reply:That thing looks like it will beat the crap out of you! I've run many a tiller on hard packed clay but that thing makes that sound like kids play. I know that this is a site for new projects but I think time and money would be better spent on RENTING a big one for the weekend and knocking out all you can. I've used those and had very good results. You pull it with your truck and IT does the work. I'm not a lazy man but God made machinery so we wouldn't have to work so hard.. While it looks like a fun project it has limited uses unless you were going into business and then I would definitely so go big. Just my .02.
Reply:I just watched a couple videos on youtube on these small stump grinders and it doesn 't look like much work at all, just swing back and forth.  Ya it will take a lot longer than renting a big stump grinder.  Personally I hate renting things cause I feel like it's a waste of money.  If one of these can be bilt for 4-600 bucks it would be well worth it in my opinion, you will have it for a long time to use whenever you want.  I borrowed a rototiller from a friend to do my moms yard after regrading it.  It was clay packed down with a bobcat all day.  His was a troy bilt forward rotating tiller, later found out those where for existing gardens.  I never knew there were more than one kind of tiller.  After getting my butt thrown around for a couple days I did some searching and ended up buying a troy bilt counter rotating tines tiller.  That thing was amazing, just hold it with one hand and it goes right threw, because the tines turn oposite of the wheels it doesn't pull at all.  I think this stump grinder is a reallistic project and will work good.  Depending on what materials you have on hand it won't cost that much.  The engine, clutch, and teeth are going to be the biggest costs.  The rest is just steel, bearings, tires, a belt, and some odds and ends.
Reply:For teethe, you need a pocket and tooth, the disk it just a big slab of steel.  The teethe are a high wear item.  On a small grinder, you need many, as once you hit a rock your productivity will go down drastically.Look up greenteeth.
Reply:Been looking at teeth.....the greenteeth are beyond my hp range according to the manufacturer.  I think I'll start with the welded on 1/2" shank lathe tooling in the beginning.  If it grinds stumps then I may go with the 1/2" pockets afterwards.  I do plan on staged teeth.  4 sets of three on each side, all equally spaced, and staggered half a space from one side of the wheel to the other.  That is IF I go ahead with the project.My name's not Jim....
Reply:I did two "big"  pine, didn't coast anything, very little work involved, I put a pile of coal (real coal, not the barbecue stuff) torched it up and went to bed next day i put more coal on it to finish it off. I know u city boys can't do that, but it was pretty easy and fast.....
Reply:Originally Posted by 1awert1I did two "big"  pine, didn't coast anything, very little work involved, I put a pile of coal (real coal, not the barbecue stuff) torched it up and went to bed next day i put more coal on it to finish it off. I know u city boys can't do that, but it was pretty easy and fast.....