2 now. The Oregon (Tecomec) as well as a Chinese copy (Mophron) which is an exact copy of the Oregon but costs 1/2 of the Oregon grinder. I bought the second one, just for setting Rakers, and it will spin a Diamond Wheel CBN Raker wheel exclusively. The loops seem to be finding their way to the shop along with the chipper knives, I'm buried in loops and knives presently. Around here, no one grinds chipper knives and the cost of thru hardened commercial chipper knives has went through the roof so it's advantageous for arborists with commercial chippers to get their knives ground, much cheaper than new sets today. I'll only grind Bandit, Chipmore and Vermeer knives as well as older style drum chipper knives. Won't grind Cone Head chipper knives or anvils. Currently at 50 cents a linear inch for each cutting edge and 5 bucks per loop up to 20" bars. That may change, I'm considering increasing the price to 75 cents per inch of cutting edge and 7 bucks a loop, depending on how bad the loops are or how bad the knives are. Some arborists run their knives way too far and then they require extensive regrinding, sort of like consumer saw chains. Dull is dull, don't push it.
Exactly. 75 cents is good. I don't understand why people push cutting edges so far into the dull territory. I hear "it was still cutting" a LOT. No, it was not cutting, it was grinding.
$ .95 per inch on knives- Grinding wheels have tripled in price in the last few years. 20 years back my big grinder wheel was $75 now it is$175 + shipping this is a 10" inserted nut cup wheel, 2" face . I can run 4 12" knives at one shot. most of the newer units use double edged knives- these have to be matched center line to edge both sides the same. There is also a minimum center to edge length that one has to be mindful of. grinding the knives less than that results in the unit jamming. Bed knife( or beater bar) also need attention. some of these are very simple others have 8 grinds on them primary and secondary ( clearance) times four sides. Single edge knives are around 40 degs bevel, double edge around 32 deg. for the most common units. the steel is tough but can be hand filed. some have a back side bevel as well.
Actually called an anvil. I have a couple of the wheels on the shelf btw. Why I limit myself to Bandit, Morbark and drum chippers. The center to edge isn't that important as the knives mount with the backside in the feed opening, so long as you remove the pitch buildup and the flat side is clean and bright, it's all good. Right now I have about 100 knives to sharpen. Big ones, small ones. All the double edge knives I run are through hardened. New ones ain't cheap either.
yep, just could not think of it at the moment. when the double edged knives get too short the chips start to jam up on the mounting area of the knife. With that drum/ plate the knives are on spinning at ?x1000 rpm keeping the knives the same keeps the balance of the assembly, nasty things happen when out of balance. Only 30 or chipper knives here right now, several hundred stump teeth, apx 100 chains, 20 0r so carbide tipped saws, a 4'x4' paper cutter that i have to make a new bottom knife for, around 100+ of demolition chisels to grind and a few other items as well. Never a dull moment well at least after i get through with them. Of course somewhere in this mess I have to make time to css fire wood, put new shocks and some bushings on the truck, replaced the valve on the splitter , sharpen apx 60 drill bits for my shop, mow the weeds, replace the garbage disposal ( I hate plumbing work)
Plumbing is nicer than being an electrician. With plumbing if it leaks you get wet. With electricity, if it leaks, you get dead.... I'm under 15 miles from Green Manufacturing and I have their Wearsharp teeth and pockets on my stump grinder and I resharpen them myself using a diamond wheel and a vertical mill. I can buy from them direct but I still resharpen them because I'm inherently cheap. I can get 3 grinds on the Wearsharp teeth as a rule but then I'm careful not to grind rocks or trash either. Ever since I bought a stump grinder, seems like I've gotten a lot of new friends... Balance isn't an issue because before a customer picks up knives, I've marked the edge of the mounting hole to the cutting edge of the knives so they can use that figure to install them in a balanced fashion. No matter what you do, you will wind up with shorter and longer grinds, depending on how abused the knives are as in how much trash was run through the chipper before changeout and you and I both know about changing knives or the lack thereof. One thing I learned pretty quick was, no matter if you grind them in sets, most contractors just put them in a box and grab whatever and install them, no regard as to sets or anything else. I've had knives I refuse to grind, they were so bad. Some looked like the owner tried to chip a cold chisel. I have my regular customers trained. They change them out regularly. Thought about doing brazed carbide chipper teeth but I have enough to do without adding to it. Bad enough I have to do my own. Just got an inquire from a local Stihl saw dealer about grinding chipper knives. Told him I had more than enough work as it is. Dull knives in milk crates and chain loops in shopping bags seem to be my specialty lately. I don't even heat with wood, don't want to. Biomass mixed with free corn is much easier. The farm consists of a large woodlot and tillable fields and I give all the wood I cut away. Have a retired friend who takes it all, splits it and sells it to the local campgrounds, it's his extra retirement income and I'm good with that. I buck everything over 3" in diameter into 24" lengths and he comes and gets it. I get to sharpen his chains as well or at least the ones that aren't carbide teeth.
Chippers are very sensitive to imbalance. I worked on one several years ago that shook/vibrated horribly. The diesel tank was cracked, the spout mount was cracked, everything had vibration damage. I welded the fuel tank, fixed the spout flange, and then proceeded to balance the drum. It was several pounds out of balance. I welded large steel chunks to the sides of the drum and got it within an ounce. The owner couldn't believe how smooth it ran. It had twice the effective hp when chipping and would eat logs that previously would have required pulsed feeding. No more vibration either. You could put your hand on it and feel the engine running. Keep those chipper drums in balance and they work MUCH better.
Never had the occasion to work on one myself. All the chippers I sharpen knives for are self feeders anyway.
I do not repair chippers. I have been called on occasion to find a particular problem. Vibration stress is something I am familiar with from another time and how it can destroy expensive machines in short order. There is a good number of the old chuck and duck units out there. Trashed knives from unchippable material is something i see all the time, 99 % of the time it is from the groundies shoveling the last bits in to a unit rather than walking 10 ft to toss in truck. Brazed on carbide on chipper blades- not a good idea, I have seen planer knives where the carbide has litterly been peeled off just from knots. Just think shrapnel I had a couple pictures of the inside of a chip box after a full tool box went through the chipper- no one hurt thankfully. The chipper was pretty well trashed.
