We asked experts from several leading manufacturers: “If there’s one thing you could remind tree care professionals about maintaining their stump grinder properly, what would it be?”
Here’s what they had to say:
Tree Care Products Business Unit Director/Morbark
Make sure to keep the cutter teeth sharp — this gets overlooked all the time. While the tooth may look good, it can get rounded and dull. This can put undue stress on the bearing and cutter shaft. The cutting teeth are the heart of the machine and need to be looked at daily.
The sole purpose of a stump cutter is to remove tree stumps in an efficient manner. This is true regardless of the machine’s horsepower, how that power is transmitted to the cutter wheel or whether the machine is on tracks or tires. The main feature of a stump cutter, which helps with productivity, is the cutter system working in tandem with the teeth — a critical component of the cutter wheel. It’s up to the user to monitor and maintain the condition of the teeth on a daily basis to help ensure they’re in good condition and being used for efficient operation. Vermeer offers its Yellow Jacket cutter system on all stump cutters. This can be a benefit to operators, as it allows the teeth to be rotated and is independent of the tooth pocket. To help ensure smoother operation, keeping the teeth in good condition will help extend the life of the machine.
Technical Support Engineer/ Steiner Tractors & Schiller Grounds Care
Make sure the teeth are sharp so you don’t waste your time with a dull stump grinder. If your grinder is dull, a stump that would have taken you two hours could take you four to six hours. Dull teeth can also decrease fuel economy and increase stress on the machine. Users should check stump grinder teeth daily, or at least after every use. Look for cutters that are dull, bent, missing or broken. When sharpening, don’t sharpen the carbide tips themselves. Instead, sharpen the heel of the bit so that the carbide tip has room to grind against the stump. In addition, make sure the drive to the wheel is in good condition and that all belts have proper tension.
Service Manager/ Rayco
Maintain the cutter teeth. Dull teeth not only slow down the time it takes to cut the client’s stump, but the grinder uses extra fuel. Dull teeth will shorten the bearing life and cause undo strain on the cutter head drive system. Teeth should be checked daily and sharpened or replaced if dull. If the carbide tip is broken or missing, the cutter tooth should be replaced.
National Sales Manager/Dosko
Proper inspection and timely changing of key components. Stump grinders are machines that operate in very tough conditions. We count on the teeth to quickly and safely remove stumps. Most operators know when the teeth need to be sharpened or replaced. In addition to the teeth, the tooth pocket and bolts need to be inspected each time teeth are sharpened or changed. Also, the bolts need replaced each time the pockets are changed. Changing pockets and bolts make sure the cutting wheel is in good shape.
Make sure the integrity of the cutting wheel isn’t compromised and that the teeth are sharp and clean. This can be accomplished with a simple visual inspection before startup. An operator should never start a stump grinder with any evidence of cracking in the wheel. Ensuring that the wheel and teeth aren’t compromised will equate to more productivity, and more importantly, will help keep the operator safe. Depending on the model of stump grinder, operators should take a look at bolt holes to see if they are worn, oversized or elongated. This can cause the tooth pockets to rotate during use and potentially change the cutting angle, ultimately leading to poor cutting performance, tooth bending or breakage.