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Feature
Article September/October 2000
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When job-site access or working room is limited, it might be time to call in a small-space specialist: a skid-steer or a compact track loader. They can pay off in a big way when space is tight and time is short. By Greg Northcutt Performance
Features If you're still looking for a reason to buy a four-wheel skid-steer or a compact track loader, then you haven't talked with Morrie Krovitz of Rock River Landscaping in Roscoe, IL. He's used skid-steer loaders to move a lot of dirt since buying his first one 14 years ago. Even though he's bought five more since then, he figures he didn't pay a dime for any of them. "They save me enough in labor costs that they run for free," he says. "I'd much rather use a skid-steer loader than labor. The skid-steer loader never suffers from a sore back, and it's always there first thing in the morning, ready to work. "I can't imagine being efficient without it. It's much easier using a skid-steer loader in a tight area to get a correct grade than using a shovel and a hand rake. If you think you need a skid-steer, you probably do." That kind of owner enthusiasm has been helping drive up the annual sales growth of these small loaders at rates of about 10-15% for the past few years. What's more, while experts doubt such growth rates can be sustained indefinitely, they still expect the trend to remain positive, at least as long as the construction market continues to be strong. No wonder. Skid-steers and compact track loaders can work in areas where larger equipment can't maneuver easily and efficiently, if at all, or where tight quarters prohibit access by the bigger machines. The ability of these small loaders to turn quickly and completely around in their own length makes for fast, easy maneuvering in and among buildings, fences, and trees. That's becoming even more important as building sites shrink in size with continued development and redevelopment in metropolitan areas. But size and agility are only part of the appeal of these machines. Thanks to the long and growing list of different types of attachments available, no other single piece of construction equipment can perform nearly as many different duties. "Contractors are putting skid-steer loaders on almost every job site because they know they can use them," says Kim Robinson, sales and marketing vice president for Daewoo Heavy Industries America in Suwanee, GA. Skid-steer and compact track machines aren't afraid of work either. "Because they provide a lot of power in a small package, skid-steer loaders are taking on such jobs as swimming pool excavating, truck loading, and finish grading," notes Louis Scheidt, a Caterpillar applications engineer. "These jobs traditionally have been handled by larger equipment, such as track-type tractors, loaders, and excavators."
Kelly Moore, product manager with Gehl Company in West Bend, WI, calls skid-steer loaders "portable power units." That portability is a bonus. Unlike tractor-loader-backhoes and larger construction equipment, you can haul a skid-steer or a compact track loader on a smaller trailer behind a pickup truck. Learning how to operate them is a relatively simple process, another advantage for time-pressed contractors. The number of skid-steer manufacturers and the models they offer have never been greater. Even so, the market for these machines isn't saturated yet, at least compared to the auto industry, says Mike Fitzgerald, Bobcat product representative in Fargo, ND.
"We're still selling a large percentage of our machines to first-time skid-steer-loader buyers," he points out. "You won't find many 16-year-olds buying a $30,000 vehicle as their first car. Yet many skid-steer-loader buyers have never owned one of these machines before." Current skid-steer owners are also fueling the demand by moving up to models with more capacity for work. "In the past, contractors tended to buy smaller models as a utility piece of equipment," Fitzgerald says. "Today they're buying larger machines and choosing from a variety of attachments and options to increase the usefulness of the machines and maximize their return on investment." As demand for skid-steer loaders holds strong, the relatively small but fast-growing demand for compact track loaders is also gaining strength. Because they are designed specifically for tracks, compact track loaders perform differently than skid-steer loaders of comparable engine power equipped with over-the-tire tracks. The price and operating costs of a compact track loader, however, are typically higher than a comparably sized skid-steer loader. A few years ago you could count on one hand the number of manufacturers offering compact track loaders in the United States. Before long, you may need at least one more hand. Last year, Bobcat became the first skid-steer maker to introduce a compact track loader. Other manufacturers are likely to follow with their models, reports Rex Hayes, product sales manager for Takeuchi in Buford, GA.
"The market for compact track loaders is expected to grow very quickly. It's not a flash in the pan. Compared to skid-steer loaders, compact track loaders offer more traction, flotation, and stability. About half of our customers are supplementing their skid-steer loaders with a compact track loader to do more of the excavating work," he adds. As skid-steer and compact track loaders take on more of the work at job sites, they're becoming more powerful, more comfortable, and more convenient to service and maintain. Depending on make and model, you can buy a new skid-steer loader with such features as:
"We sell very few baseline machines," Fitzgerald points out. "The many options and accessories available for today's skid-steer loaders allow you to match a machine to your individual needs for maximum use and versatility."
Horsepower rating by itself isn't an accurate measure of how well a skid-steer or compact track loader will handle grading and excavating work. Much more important is how efficiently and effectively this power is used to dig, cut, push, lift, and dump dirt. Bucket breakout force, measured at the cutting edge of the bucket, indicates the power available to roll the bucket back after digging into the soil. It's not critical when digging into loose material, but it becomes much more important when excavating compacted ground. More breakout power means less time to fill a bucket and higher production. Engine torque curves provide another measure of productivity. "If torque increases as rpm decreases when you're digging into a pile of dirt, the engine will recover back to operating speed more quickly for faster cycle times," explains Robinson. Rated operating capacity indicates the ability of a loader to safely lift and carry material. It equals no more than half the weight of the load in a standard bucket that would cause the skid-steer loader to tip forward. For compact track loaders, the rated operating capacity is 35% of the tipping load. "Rated operating capacity is affected by machine weight, wheelbase, and lift-arm design," Fitzgerald describes. "A heavier machine can lift and move a heavier load than a lighter machine. Longer-wheelbase skid-steer loaders tend to have higher-rated operating capacities. A vertical lift path keeps the load closer to the machine. So a loader with this lift pattern can lift more than an identical loader with a radius lift path. Also, a vertical lift path gives you more reach at maximum lift-arm height for loading into truck boxes." A skid-steer loader with a conventional wheelbase is more maneuverable because it can turn in a shorter radius than a loader with a longer wheelbase. A longer wheelbase offers a smoother ride, however. Tractive effort indicates how much wheel torque is transmitted to the ground, where the work is done. But, mentions Tom Banner, product information manager with Case Corporation in Racine, WI, tractive effort is affected by several factors. "It's very dependent on wheel traction, which in turn depends on the size of the tire footprint, the type of tread, and the ground surface, whether loose or hard or smooth or rocky," he says. "A good skid-steer - loader operator starts to raise the bucket when it starts to break out the dirt. This puts more weight on the front tires for more traction. If your tires spin when breaking out, you have more tractive effort than you need." "Heavier skid-steer loaders generally produce more tractive effort as long as adequate horsepower and axle torque are available," adds Scheidt. "Hydraulic cycle times impact productivity too. For most experienced operators, faster is better as long as it's controllable." Tire design affects traction, flotation, and ride quality. The tires must withstand the wear and extra pressure on the sidewalls exerted every time a skid-steer loader turns. Tires with extra-wide tread can keep a skid-steer loader moving on softer ground. As with foam-filled tires, those with a soft fill eliminate flat tires. But unlike the hard ride of a foam-fill, the ride of a soft-fill is like that of a pneumatic tire. And soft-fills are retreadable. One manufacturer offers a tire that allows a skid-steer loader to continue operating for a time even when the tire is flat. John Killilee of Sunbelt Rentals in Charlotte, NC, has been using Michelin's XZSL Stabil'X tires - the first tires made specifically for skid-steer loaders - for about a year on his company's rental machines. The steel-belted radials "are pretty much puncture-proof," he attests, a feature his customers also appreciate. "It's a lot smoother of a ride, and they don't have the downtime because they're not getting flat tires." He used to use foam-filled tires, which cost about $15 less per tire but lasted an average of only six months in the construction and demolition work where most of his customers use the machines. With special rubber compounds to resist cuts, the XZSL tires are showing little wear after the first year. "They're lightweight, so it's less wear and tear on the equipment, and they don't leave any black marks on the concrete, particularly on concrete driveways. I don't put foam-fill on anything anymore." In addition to the normal working speeds, some skid-steer loaders offer a faster transport gear to save time when traveling between job sites. Comfort and Convenience Features
"Fine grading requires small changes to the bucket cutting edge," states Scheidt. "Low-effort controls can provide excellent control of the bucket. When coupled with a long wheelbase, it makes grading tasks much easier and more accurate." All manufacturers offer skid-steer loaders with built-in float control. This allows the loader arms to move up and down when backgrading, permitting (for variety) the bucket or attachment to automatically follow the terrain. That can produce a nicer grade when grading dirt from roadside to curb and gutter, when working next to a house or other building, and when leveling for a foundation. Among other features to check:
To minimize downtime, skid-steer and compact track loaders used for grading and excavating work should be engineered and built to withstand heavier duty, say the experts. Selecting durable components that require minimal maintenance and few adjustments can pay off with less downtime. "Look for good protection of hydraulic hoses and cylinders, wiring, and grease fittings," Scheidt advises. "Don't forget the work tool. Buckets that have a formed back wrapper will load best. Full-length skid bars on the underneath side provide the additional floor rigidity and wear resistance needed for back dragging. Bolt-on cutting edges will protect the base edge and extend bucket life." Proper, timely service keeps a machine operating at peak performance. Look for easy access to service and maintenance items like fluids, filters and grease fittings, the fuel injection pump, and hydrostatics. Pin joints that distribute lubrication around the entire pin rather than just on top will give superior service in tough applications, advises Scheidt. A cab that is simple to raise and lower makes it easier and less time-consuming to reach the hydrostatic drive system for servicing. Greg Northcutt is an editorial consultant to the International Erosion Control Association and a writer on construction issues.
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