Trenchers for Mini Excavators: Swap the Popular Bucket and Get Digging with a Trencher Attachment

Trencher attachments are the perfect tools for operators who need to slice through the dirt with precision and ease. They help everyone from contractors and landscapers to maintenance crews and municipalities dig narrow trenches (anywhere from 4 to 12 in.) for installing irrigation systems, power and water lines and even performing road repairs or general construction tasks. While these attachments are commonly found on skid steers and compact track loaders, they can also be used on mini excavators. Yes, it’s true. Operators can outfit their mini excavators with a trencher and reap the benefits of this hard-working attachment.
“Trenchers are used to dig trenches for utilities such as irrigation, plumbing and electrical, as well as for foundations in construction,” says Beau Ellingson, sales manager for Digga. “Some of the advantages in using a trencher attachment is the speed at which an operator can dig a trench. It is faster than using a bucket in most circumstances. The spoil produced by a trencher is much finer than spoil produced by using a bucket. As a result, backfilling the trench is easier and reduces the chances of ground sinkage caused by air pockets and poorly compacted ground.”
Before you hop over to an equipment dealer to buy a trencher attachment, it’s important to know where to start so you get the right tool for your excavator. First, look for a quality-built product from a reputable manufacturer. Companies such as Digga, Caterpillar, Bobcat and Auger Torque all offer trencher attachments for mini excavators.
Next, Ellingson says matching the correct hydraulic flows and pressures to the excavator is critical in getting the ideal balance between chain speed and torque. A 3- or 4-ft trencher can typically be powered by a standard hydraulic system whereas a 5-ft or larger trencher will likely need to be powered by a high-flow hydraulic option. Ellingson points out that two-way hydraulics are required to run a Digga trencher, and bolt-on two-way valve solutions are also available.
“Three-foot trenchers for machines up to 4.5 tons require 13 to 25 gpm,” Ellingson says. “Four-foot trenchers for machines up to 8 tons require between 16 to 30 gpm, while 5-ft trenchers require between 28 and 45 gpm.”
As for size options from manufacturers, Digga offers 3-, 4- and 5-ft booms with chain width options starting at 4 in. and running up to 12 in. on the 5-ft model. Bobcat’s MX112 trencher features a 3-ft boom, a digging width of 4 to 8 in. and a dig depth of 2 ft. Auger Torque’s MT 600 and MT 900 trenchers are ideal for 2.5- to 5-ton excavators and dig widths from 4 to nearly 12 in.
Ease of use is also important, and Ellingson says customers should look for a model with an adjustable depth foot and a crumber bar, which allows you to start trenching with the bar in the ground.
“Trenchers with a foot preset to a particular depth eliminate the need for an additional person to monitor the trench depth,” Ellingson says. “Once the depth is set, the operator can effortlessly maintain depth while the crumber bar ensures the bottom of the trench is flat and clean.”
Finally, operators should make sure to choose the right tooth combination for the ground conditions they plan to encounter. Ellingson says the wrong tooth will be inefficient and burn out, costing the operator time and money. Digga offers three chain options: Earth, Combo and Diggatac.
“The Earth chain is ideal for soft, clean ground while the Combo chain is suited to most ground conditions including hard soil, shale and rocky ground,” says Ellingson. “The Diggatac chain should be used for trenching in frozen ground, shale and asphalt.”
Auger Torque has similar chain options: Earth for soft ground, Combi for mixed terrain and Tungsten for hard or frozen ground.
Pam Kleineke is managing editor of Compact Equipment.