Dedicated to Trenching

Good utility contractors need to be able dissect the soil like surgeons, implanting utilities precisely and quickly to keep our services circulating. On a cramped urban project site, professionals need the best tools to maneuver between cluttered systems of underground utilities without disturbing vital arteries or leaving a big scar.

With a steady dedicated trencher in their tool belts, utility contractors can successfully dig and install water, sewer, fiber, gas and other subsurface utilities (without a lot of restoration). Since the 1950s, utility contractors, cities, rental shops and large estate owners have chosen the compact trencher as a great, less expensive machine choice for utility work. Even with the influx of digging machines like compact excavators and mini backhoe loaders, the compact trencher still continues to find steady jobs on utility projects today. And why not? Besides their precision and power, trencher equipment often trenches more feet per hour than either a mini excavator or backhoe

The industry yields two main types of small trenchers — pedestrian and compact ride-on units — engineered for shorter utility runs and restrictive jobsites often encountered by urban contractors. Within those two categories, there are three main manufacturers selling compact trenchers – Ditch Witch, Vermeer and Astec. Chances are that trio of manufacturers has an ideal dedicated digger that fits your crew and job sizes

It’s just a matter of building your bedrock of market knowledge before you step onto the dealer lot.

The Pedestrian Trencher

Walk-behind trenchers were the original short-run, compact trenching dynamos, invented by utility machine manufacturer Ditch Witch in 1950. Walk-behind or “pedestrian” trenchers are small, easy-to-maneuver, dedicated digging machines that are excellent for small installations in tight quarters. Ranging in price from $3,000 to $15,000, pedestrian trenchers utilize gasoline engines that typically range from 6 to 30 hp and down, providing enough capacity to dig trenches up to 2 to 4 ft deep and up to 6 in. wide.

“There are really three popular groups of pedestrian trenchers — 12-in., 24-in. and 36-in. digging depths,” says Brent Bolay, senior product manager for trenching products at Ditch Witch. “Those depths have a tendency to match up to the horsepower class that is available. Those horsepowers are 6- to 9-hp class, 10- to 15-hp class and 18- to 23-hp class. We think the most popular is the 10- to 15-hp range.”

That popular horsepower class offers an excellent size to power ratio. Those 10- to 15-hp pedestrian trenchers typically dig 24 in. deep and that’s often a minimum depth requirement for many utility contractors to install product safely. It’s also a trencher in a category that’s relatively inexpensive — $7,000 to $10,000. With those prices, pedestrian trencher sales have been steady for decades — the biggest growing market being rental.

“The trencher market is not a retail reporting market. However, North American shipments show that nearly 50 percent of the market is 30 hp and down, which we feel is mostly the rental market,” explains Bob Wren, training manager with Astec Underground — manufacturer of the former Case line of trenchers, which the company purchased and re-engineered in 2003.

Walk-behind trenchers are popular rental items because of their small size, easy maintenance and dedicated nature. When a professional does look to buy a model, job requirements will dictate what size unit is needed. Dig depth, width and trench length are always determining factors. The biggest options will be in boom and chain configurations (and occasionally an engine choice). The tiny Vermeer RT60 mini-trenchers, for example, offer a choice of a 6-hp Kohler or a 5.5-hp Honda engine, as well as
boom sizes of 4, 8 or 12 in. The popular 13-hp Astec 60 trencher is perfect for light trenching jobs with either a 24- or a 36-in. heavy duty boom (the choice is yours), and the Ditch Witch 1230 has the option of a 24-, 30- or 36-in. big dig boom.

Pedestrian trenchers should also have choices in trencher chains. Digging chain choices may include the style of chain and its teeth. Digging chains can be separated into three main categories — side plate, K-style and knuckle chains. Side plate chains dig with teeth that are lined up side-by-side, bolted to the side plates of the chain horizontally. Side plate chains are good for normal ground conditions. K-style plates (or flat-base chains) have digging teeth that are good for harder ground conditions. Knuckle chains use a no-roller, no-thimble chain that is all one piece, adept at surviving hard ground conditions.

Teeth (also called cutters and bits) can be either welded or bolted onto the chain. The most widely used teeth are cupped cutters, which are designed with a front-cutting edge that’s shaped to actually dig and move spoil out of the ditch. But cup cutters are not designed for hard ground. For serious soil conditions, buyers can equip chains with gnarly teeth that have cool descriptors like shark, alligator, mining or rock and frost cutters. Often, chains can have welded-on teeth for maximum performance in extreme conditions.

Besides boom and teeth, shoppers also have a choice of a mechanical or hydraulically driven trencher. With the evolution of hydrostatic drives and hydraulic boom lift, walk-behind trenchers are becoming easier and more efficient to use. For decades, mechanical trencher drives were the standard on pedestrian trenchers, using gear boxes, shafts, pulleys, chains and sprockets to drive the digging chain and move the boom. Hydraulic drives have fewer maintenance points, less controls for the operator, an infinite number of chains speeds to choose for trenching and they are more tolerant when taking big shock loads, “The ability to reverse the digger chain takes a lot of stress out of the machine when obstacles are hit in the ground,” says Todd Roorda, RT solutions specialist with Vermeer Mfg. Co.

Manufacturers say a reversible digging chain is one of the biggest advantages of hydrostatic drive systems. If a crew comes across a tree root, a large rock or an unmarked pet cemetery, the operator can pull a lever and reverse the chain out of a sticky situation. While the majority of drives today are hydraulic, there are models still available with mechanical drives (good examples are the Ditch Witch 1030 and 1820 models). Some manufacturers, like Vermeer, even have unique drive systems — like its patent-pending Ground Drive Assist, which helps the operator trench a straight line, reducing the amount of physical labor required while trenching.

Hydraulic boom lift has also made pedestrian trencher operation easier. Some mechanical trenchers were designed with a hand-crank to raise and lower the boom, requiring the operator to maneuver around that sharp trencher boom. But with hydraulic lift, operators can easily raise and lower their trench boom from behind the handle bars of their walk-behind.

Other factors for your purchasing decision formula will most likely revolve around a good dealer and the exact
features offered by the manufacturer. Extras like trench depth levers, loading handles, comfortable and steady handlebars, color-coded and user-friendly controls, digging chain operator presence control switches and a well-balanced
and brawny construction will always sweeten the deal.

Get Your Ride-On

When bigger horsepower, a wider depth and a deeper trench are the game plan, a ride-on compact trencher might be your weapon of choice. Ride-on trenchers can breeze through depths of 4 to 6 ft, trenching 6 to 12 in. wide, using 35- to 50-hp engines. Compact ride-on trenchers can be a bit more expensive too — from $24,000 to $60,000, depending on horsepower and how they’re equipped.

Besides more power, a bigger trench and the chance to sit while you work, ride-on trenchers also offer the operator the use of some attachments. Vibratory plows, backfill blades and backhoes are popular add-on tools for ride-on trenchers. Of course, theynot quick-attaching type of implements.

“Attachments are offered, but they are not the types of attachments that are easily exchanged in a few
minutes like what you see on a skid steer,” says Roorda. “Optional attachments, including vibratory plows and backhoes, can be switched out on machines, but it takes a little more time.”

Some ride-on trenchers also have the option of tracks, instead of wheels. Much like their skid steer/track loader counterparts, a dedicated track undercarriage on a ride-on trencher offers more flotation and better traction, but it may cost more initially and have more maintenance upkeep.

“These [track] machines are just hitting the market and are being positively accepted,” says Roorda. “Some advantages are an extended working season, meaning those days after a heavy rain are now days that the track machine can be out working due to its increased flotation. Track units also cause less ground disturbance when working on finished lawns and offer increased side hill stability and better ability to cross open-cut trenches.”

But the market for track trenchers is limited. There are only so many applications that justify the higher operating costs and price tag.

“I think that there is a market for some track units. Our most popular unit, the TF300B, at 18.5-hp is sold as a footing trencher,” says Wren. “Other than that, I do not think that the volumes are there to justify us manufacturing other units.”

All of these types of trenchers — no matter if they use wheels or tracks — are most likely using a hydrostatic drive today, instead of the traditional mechanical drive (just like their pedestrian brethren). Other popular options might include advanced steering systems (four-wheel, rear-wheel and all-wheel steer), boom lengths (often from 36 to 60 in.) and chains (cup cutter, shark, alligator, etc.). Creature comforts also come into more play with ride-on trenchers. An ergonomically designed operator’s station with smart instrumental panel, easy-to-use controls, a comfortable seat, plenty of leg room and easy on/off access are all great selling points for a ride-on trencher.

Other popular trends are often hard to track in the trencher industry. The trencher market is cyclical and industry numbers on units sold is nearly impossible to glean, but for major manufacturers like Ditch Witch, Vermeer and Astec, trenchers will continue to be one of their major product offerings.

“Trenchers in general from 13 hp to 100 hp have always been a steady market,” says Wren. “It’s not really a growth market, but as long as housing stays good, the market will stay with us. With only three major players in the marketplace, there is enough business for everyone.”

Keith Gribbins is a managing editor of Compact Equipment.