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Keeping Your Wood Chipper Running Smoothly

Maintaining your wood chipper after purchase is vital in ensuring you receive years of use from your device.

Gary McKeag, a brush chipper service technician at the Vermeer Corporation, recommends following these two valuable directives will make a significant impact in promoting strong, lasting machine performance.

Foremost, he suggests greasing the cutter drum or disc bearings after use, when the machine is still warm. Fresh grease should be applied until the old grease emerges. Performing this task rids the machine of potentially damaging debris, and expels moisture that might corrode the bearings.

Secondly, it's imperative that the knives be checked after each use to confirm they remain damage-free. Search carefully for debris buildup. The knives provide the all-important chopping feature of the machine, so they must be carefully maintained to operate in peak condition. If you delay until function is reduced, your productivity will diminish, and the bearings will suffer. In addition, remember to periodically confirm that the torque on the knife mounting hardware is sufficient according to operation instructions.

McKeag also recommends that daily brush chipper owner/operators should pay regular attention to the engine compartment and radiator. With new emission standards on the rise, higher engine operating temperatures are common, therefore demanding larger radiators. Ensuring that the radiator remains unclogged is essential in avoiding engine overheating that could lead to a shutdown. Blowing out engine compartments helps reduce high temperatures and "fines" that can pass through the radiator. Too much debris behind the feed rollers prevents full functioning. To restore your machine to pre-debris standards, deploy an air compressor or leaf blower. The fact is that clean machines always run better. Once the machine has been cleaned, you can easily confirm that all shielding, switches, control bars and hitching components are healthy.

Lastly, take a walk around the machine in advance of operation. Note any aspect that could reduce productivity, such as a loose hydraulic line, clamp or fitting, a worn hose or missing hardware. Then, make the repair, or arrange to have it done professionally.

Care for whole tree chippers is somewhat more involved. According to the Bandit Industries website, it's crucial to ensure all knives are aligned with a properly adjustable anvil. Imperfect knife and anvil maintenance detract from fuel economy and production, and add to machine wear-and-tear through the increased vibration produced by misalignment. Therefore, every time knives are sharpened or replaced, the anvil must be readjusted to ensure proper clearance.

It's also important to ensure the correct shutdown procedures are followed prior to starting any maintenance project. First off, always wear cut-resistant gloves and safety goggles. Once your hands and eyes are protected, disengage the clutch and wait until the disc or drum comes to a complete stop. Then, insert the disc/drum pin, remove the key (storing it somewhere safely), and disconnect the battery.

Changing knives is a two-person task. Remove the knives from the holder, after which you or your task partner should inspect the drum for secure welds, excessive wear, impact cracks, elongated bolt holes, and the condition of the knife bolt threads. Once the knives are out of the machine, clean the knife pocket with either compressed air or a wire brush. Be certain to thoroughly clean the pocket before you reinstall any knives.

A reminder: knives should always be professionally sharpened in order to maintain the correct angle and dimension specifications. They should also be replaced in sets, with the set being determined by the degree of sharpening necessary. Further, the new knives should be reinstalled opposite knives with a similar purpose to help maintain balance. It is unsafe to allow knives to wear beyond the absolute minimum specified distance from centerline of the bolthole. All new and sharpened knives must be rebabbitted to ensure they fit correctly. Consult your manual for proper babbitting procedures.

When you have safely babbitted your knife, place it in the knife pocket and place the knife holder on top. Slip the bolts into the threads and tighten. Make sure to tighten them to the correct torque as specified in your manual.

Next, remove the drum/disc pin and turn the drum/disc to the next knife pocket. Reinstall the pin and then install the babbitted knife, tightening each bolt to the correct torque.

Remember that all hardware must be replaced after four or five knife rotations. This helps ensure that your bolts will remain tight in the disc or drum. Be sure to use only the approved hardware for your machine.

To check the anvil clearance, carefully rotate the disc or drum, checking as each knife passes the anvil. As the knife approaches the anvil, pause and check the clearance with a feeler gauge. Be sure to check the clearance along the entire length of the knife.

To adjust the anvil, loosen two hex nuts on the inside or the outside of the anvil puller block. Consult your operator's manual for the puller block location. For anvils needing adjustment closer to the knife, loosen the outside hex nuts. If the anvil needs adjusting further from the knife, loosen the inside hex nuts. Once the hardware is loosened, adjust the anvil to the correct clearance and retighten the hex nuts to the correct torque.

Proper care will ensure that your tools provide optimum performance. To get the most from your investment, carefully follow manufacturer maintenance guidelines. Your machines will reward you with consistently peak performance.