Invasion of the Bark Eaters
Long wooden limbs lay lifeless in a pile. Stumps shiver in the cool breeze, and the decay of decimated bark fills the air.
Just a few feet away, the mouth of a metal monster gapes open nearly 20-in. wide with teeth spinning at 1,900 revolutions per minute. It’s a tow-behind brush chipper, and it’s an essential piece of machinery for landscaping and construction crews who need a monster machine to clear brush.
Perfecting the technologies of brute force, manufacturers such as Vermeer, Rayco, ECHO Bear Cat, Morbark and Bandit have fine tuned the “chuck and duck” chippers of old into precise brush cutting machines that are safe and productive.
“In the early days, before feed rollers, you could see right into the drum [of the brush chipper]. We used to call them chuck and duck machines because you would practically have to duck as the material was pulled into the drums,” says Chris Nichols, sales manager for Vermeer.
Moving away from its past shortcomings, today’s brush chipper can handle material diameters ranging from 4.5 to 20 in. and offers a variety of safety features (from easily-activated stopping mechanisms to auto feeding) that will keep your crews working safely. When stepping onto the dealer’s lot with hopes of taking home your very own chipper, you need to match the machine to your job demands.
“Brush chipper capacity is rated by the size of the feed opening. There are commonly 4.5-, 6-, 12-, 15-, 18- and 20-in. chippers,” Nichols says. “The smaller 6-in. chippers are mostly used by homeowners and landscapers, the 12-in. chippers are used by tree services and tree contractors and the 18- and 20-in. chippers you see more on site prep and land clearing jobs. The choice of chipper absolutely is relative to the job. You need to have an understanding of the material you’ll be working with.”
Area 51
Unlike the secret government-controlled testing facilities of old, your brush chipper’s proving grounds will be on a jobsite — where everyone will know if your chipper can handle the material you throw at it. In order to find the perfect size brush chipper, avoid costly downtime and get the most bang for your buck, size the material of the brush to the size of the chipper.
“Obviously, if the brush is too big, it’s not going to fit through the feed hole and the operator will end up having to pull it out and set it aside,” explains Nichols. “You might think that you’ll have a maximum of 10-in. diameter brush, but when you get [on the jobsite] and there is a section of 15-in. [brush], you’re going to have to set it aside and cart it off later.”
Unlike other machines where “compact” is the name of the game and the goal is to get into tight jobsite crevasses, “bigger is better” is the typical motto in the brush chipper world. Alas that’s not always true. If you feed the need for the biggest brush chipper on the block, consider you might be using too much horsepower and gas, not to mention you’ll have heavier towing requirements and a larger upfront cost.
“Usually, a 12-in. chipper is rated for occasionally chipping 12-in. material and [chipping] 8- to 10-in. material non-stop,” says Kevin Covert, sales and marketing manager for Rayco.
Though the size of the brush chipper is the most important match making specification, you’ll also have a couple choices within the chosen brush chipper diameter capacity. Within the genus of brush chippers, there exists two primary species that have evolved over time — disc- and drum-style chippers.
The drum and disc are what the chipper’s teeth, or knives, are mounted to and they spin at furious rates to crush stubborn debris. Drums are typically seen in larger chippers to keep the size of the machine to a minimum. For example, if you had a 20-in. disc chipper, you would need a disc that had a clearance of 20 in. both above and below its center bearing, which would make for a beastly 4- to 5-ft tall disc.
“Drum [chippers] seems to be what people want. You tend to get a more uniform chip and it can handle any type of material — soft, hard or stringy. As the drum passes the anvil, the knives are staggered, so they are passing the anvil all the time. With a disc, it’s usually at an angle with 6-in. of dead space on one side and a foot and half of dead space on the other,” Covert explains. “Drum chippers were first made back when they were called chuck and ducks, then the disc-style became popular in the ‘80s. In 2002 and 2003, drum made a come back and that’s what the market is predominately made up of today.”
Discs, being smaller and lighter, are commonly found in smaller chippers. In addition to keeping the chipper size down, discs also have a quick recovery time when under an intense load. There have been recent strides in disc chipper technology such as the cantilever disc design offered by ECHO Bear Cat, which chips fibrous and stringy vines without wrapping up inside the machine.
What could possibly be powering these tree-shredding brutes? With the fuel epidemic sweeping the country, there are now two common engine options, both gas and diesel. The gas engine option is primarily for the availability of fuel. It’s a great solution for a homeowner who might not have a diesel fuel source near by and already has gas on hand for lawn mowers and weed whackers. For larger chippers, diesel offers improved chipping horsepower and life. Considering a gallon of diesel goes further than a gallon of gas, it’s no surprise that diesel has usurped gas as the king of brush chipper power.
Space Age Technologies
The future-shaping engineers of the 1950s laid the groundwork for today’s brush chipper technology. While we don’t have flying cars to pull our hovering chippers yet, the safety features have improved dramatically. Perhaps the most important technological advancement was the advent of auto feed rollers. Practically every manufacturer has an auto feed system; Vermeer calls its SmartFeed, while Rayco calls its VersaFeed and ECHO Bear Cat has its hydraulic feed units.
“When you feed the chipper, the rollers take over and feed to the disc or drum. It stops when the material needs to stop. If the engine rpms are dropping, the chipper will stop feeding the machine until the rpms recover. It can even reverse the material if it’s overloaded,” says Nichols.
Brush chipping is a violent application and automatic feed rollers are particularly useful in keeping your hands away from the spinning knives. In the way of even greater safety precautions, take notice of the chipper’s emergency stop. Some manufacturers have buttons that need to be pushed, while others, like Vermeer and Rayco, have a bar that stops the drum’s or disc’s rotation.
Among the other brush chipper technology, Rayco offers a fuel saver technology that revs the engine down to an idle when the feed bar is in the neutral position. It remains that way until the feed bar is engaged. Bear Cat offers digital, programmable electronic feed sensors with hour meters that monitors disc rpm to maintain optimum performance. Most manufacturers, such as Vermeer and Rayco, offer a winch technology that practically lifts the material onto the feed table for you and a sound abatement technology that silences the screams of doomed tree limbs during residential jobs.
Just make sure your adventure to the dealer’s lot to pick out your new brush chipper doesn’t turn into a story filled with embarrassment and regret — especially if you buy a chipper that is too big to be towed behind your pickup. Most brush chippers come with a towing package that includes the wiring, lights, safety chains and hitch couplers, but it’s up to you to triple check your chariot’s gross vehicle weight (GVW) and towing capacity. Most chippers can be towed without a commercial driver’s license (CDL), but when you get into the 18- to 20-in. chippers, you can end up on the fringe. So, be sure to check your state’s CDL laws.
Nothing makes stomachs drop and contractors turn pale more than not being able to mobilize a new brush devouring monstrosity. When your chipper investment will run between $4,000 for a 4.5-in. to $65,000 for a 20-in. chipper ($25,000 to $40,000 for a 12- to 15-in. chipper), you want to make sure that you get the most chip for your buck. And you’re primed to let loose your latest technological terror upon unsuspecting wooden debris.
Comments are closed here.