A chain-type skid loader trencher typically digs 3 to 5 feet deep, depending on the attachment and boom length. Mini models commonly dig 2 to 3 feet, with some reaching 4 feet. Boom length determines maximum reach, while soil conditions, chain selection, and hydraulic output affect cutting performance at that depth.
How Deep Can a Skid Steer Trencher Typically Dig?
Full-size chain trencher attachments commonly have maximum digging depths of 36, 48, or 60 inches. A mini skid steer trencher commonly reaches 24, 30, or 36 inches, and some models reach 48 inches. The exact maximum depends on the boom fitted to the attachment.
Rated Trenching Depth vs. Actual Working Depth
For pipe and conduit installations, distinguish the attachment’s digging depth from the cover required above the buried line:
| Measurement | What It Means | Why It Matters |
|---|---|---|
| Rated digging depth | Published reach in the manufacturer’s specified setup | Establishes the attachment’s depth capability |
| Actual working depth | Depth achieved to the usable trench bottom | Can change with attachment position, terrain, cutting load, and loose spoil |
| Required cover | Distance from finished grade to the top of the installed pipe or conduit | Does not include the pipe diameter or bedding below it |
Cover is measured to the top of the pipe. The excavation must also accommodate its outside diameter and any bedding underneath. For a single pipe:
Required excavation depth = required cover + pipe outside diameter + bedding thickness.
For example, a project specifying 24 inches of cover, a pipe with a 2-inch outside diameter, and 2 inches of bedding requires a 28-inch-deep excavation. Use the dimensions in your approved installation detail for this calculation.
Measure the usable bottom after loose material is removed. A crumber, the cleanup assembly behind the digging chain, helps feed loose spoil back to the chain. Also account for planned grading: removing surface soil later reduces the cover above an installed line.
How Boom Length and Chain Configuration Affect Depth
The boom and its operating angle determine how far the chain reaches below ground. Use the attachment’s rated digging depth for planning; measuring the boom’s physical length will not give its vertical reach.
Depth adjustment varies by model. Some attachments use adjustable skid feet; others use loader-arm position and attachment tilt. These adjustments also affect the spoil auger and cleanup assembly, so follow the model’s setup instructions.
Tooth style determines how the chain cuts and carries material. A rock chain improves cutting in suitable rocky ground while retaining the same depth limit on the same boom.
A deeper configuration may require a longer boom, a matching chain, and different cleanup components. Fit only a manufacturer-approved combination. Adding chain length alone cannot turn a 36-inch assembly into a 48-inch trencher.
How Soil, Roots, and Rocks Affect Trenching Performance
Difficult ground often reduces how quickly the machine can advance. A suitable setup may still achieve the rated depth, but the operator must feed the chain slowly enough to keep it cutting and carrying spoil out.
| Ground Condition | Main Difficulty | Chain and Setup Considerations |
|---|---|---|
| Soft to medium soil | Cutting soil and lifting it out | Cup-tooth chains are commonly used; inspect teeth for wear |
| Wet, sticky clay | Soil packing around the chain and cleanup components | Use the manufacturer’s recommended tooth spacing and chain configuration |
| Sand or loose soil | Material falling back into the trench | Spoil-carrying capacity and wall condition become especially important |
| Hard, compacted, or rocky ground | Greater cutting resistance and tooth wear | Consider an approved combination or rock chain within the attachment’s material limits |
Small stones, large embedded rocks, and continuous rock place different demands on the attachment. Check the manufacturer’s material limits before planning a rock cut. If the chain is intended for small stones, the job may require another tool for larger obstructions.
Treat substantial roots separately from ordinary soil resistance. Verify the attachment’s suitability for woody material, and assess the effect of root cutting near trees that will remain on site.
When the chain repeatedly stalls, reduce travel speed within the operating instructions and reassess the obstruction. Persistent stalling can indicate unsuitable material, worn teeth, or a setup problem. Shut down and isolate the attachment before clearing it or inspecting the chain.
Hydraulic Flow and Carrier Requirements
A trenching attachment for skid steer loaders needs auxiliary flow and pressure matched to its motor, plus a carrier that can handle its weight and operating forces.
Flow affects motor speed; pressure and motor displacement affect available torque. Too little flow can limit chain speed and spoil removal. Excess flow can overspeed or damage a motor that is not designed for it.
Select standard-flow or high-flow operation from the attachment’s motor specifications. Boom length alone does not determine the required flow.
For example, if an attachment specifies 15 to 25 GPM, a carrier supplying 20 GPM meets the flow requirement. A 10 GPM supply is below the range; a 30 GPM supply needs an approved setting that delivers flow within the range.
Complete the carrier match with these checks:
- Mount and locking system: Verify plate dimensions and secure engagement. Mini-loader interfaces can differ from full-size skid steer mounts.
- Pressure: Match required operating pressure and permitted maximum pressure to the carrier’s auxiliary circuit.
- Return and case drain: Check return-pressure limits and any dedicated case-drain requirement. A required case drain returns internal motor leakage through a low-pressure line.
- Couplers, hoses, and controls: Verify connection compatibility, hose ratings and routing, and any electrical control requirements.
- Weight and stability: Check approved carrier capacity and operating position. Rated operating capacity and tipping load are different specifications.
- Cooling and guarding: Confirm suitability for sustained hydraulic work and the required protective equipment.
Use the auxiliary flow available to the attachment. Total machine flow may include other circuits, and standard-flow ratings vary between carriers.
Repeated stalls can heat the oil quickly. Stop according to the manuals if overheating occurs, and investigate cutting load, connections, and cooling.
Choosing Trench Width for Different Projects
Choose width from the complete installation detail: pipe outside diameter, fittings, bedding, drainage media, and any clearance needed for joining or compaction. Nominal pipe size can differ from its outside diameter.
For pipe and cable runs requiring a narrow trench, our 6-inch hydraulic trencher cuts 6 inches wide and up to 37 inches deep. Allow for fittings and required side clearance when assessing a 6-inch cut. Connection points may need separate widening.
A French drain needs space for the specified aggregate and fabric assembly, or the full diameter of a prefabricated drainage bundle. A trench wide enough for the pipe alone may be too narrow for the drainage system.
Width also changes the cutting load. At the same depth and length, an 8-inch cut removes one-third more soil than a 6-inch cut, based on nominal rectangular dimensions. Actual spoil volume also depends on wall collapse and soil expansion; production speed depends on soil, chain, and hydraulics.
If workers must enter, or the job needs large connection pits and substantial widening, include an excavator and the necessary excavation protection in the equipment plan.
Utility Location and Safe Trenching Practices
Locate underground services before making any cut, then control the hazards around the machine and open trench:
Request utility locating: Contact 811 or the appropriate state service. Complete the required waiting period and check utility responses before digging. Follow local rules for ticket validity, tolerance zones, and digging near marks.
Locate private lines: Arrange separate locating for privately owned underground lines, such as irrigation piping, outbuilding power, and outdoor appliance gas lines. Public utility locating may exclude these services.
Establish the utility’s exact position: Marks show approximate horizontal location, not guaranteed depth. As work approaches an expected line, use the safe locating methods permitted for that site.
Keep people clear: Maintain clearance around the chain, auger, and carrier travel path. Before clearing or adjusting the attachment, lower it and follow the shutdown, isolation, and pressure-release procedures in both manuals.
Control excavation-edge hazards: Keep spoil and equipment that could fall or roll into the cut at least 2 feet from the edge, or use suitable retaining protection. Determine the loader’s operating setback from site conditions and equipment instructions; the 2-foot rule is not a universal machine setback.
Arrange inspections and entry protection: For construction work involving employees, follow OSHA excavation requirements, including competent-person inspections when employee exposure can reasonably be anticipated. Plan safe access and egress if employees will enter.
Employees entering excavations generally need an adequate cave-in protective system. Exceptions include excavation entirely in stable rock, or a cut less than 5 feet deep that a competent person examines and finds no indication of a potential cave-in.
Plan for the Deepest Point on the Route
Choose a skid loader trencher for the deepest excavation along the route. On a drainage job, calculate that depth from both the ground elevation and the planned pipe slope, including bedding. Then match the required width, soil conditions, and auxiliary hydraulics to the attachment. After utility locating and setup, check a short initial section for depth and bottom cleanup before continuing. Plan separate work for tight ends or connection pits so those details are included in the schedule and equipment choice.
Frequently Asked Questions About How Deep Can a Skid Steer
Q1. Can a 48-Inch Trencher Dig a 24-Inch Trench?
Yes, if the model supports that depth through its approved adjustment method. Check the available settings and attachment-position instructions. The spoil auger and cleanup assembly must still function correctly at the shallower setting; simply lifting the boom may affect both.
Q2. Can Two Passes Make a Trencher Dig Beyond Its Rated Depth?
No. Repeated passes from the same ground level do not extend the boom’s reach. Lowering the carrier onto an excavated surface creates additional stability and excavation hazards. Select equipment rated for the full required cut.
Q3. Can a Skid Steer Trencher Reach Full Depth Right Beside a Wall?
The boom often needs lead-in distance to reach full depth. Frame clearance, auger position, and foundation stability also limit access. Check the attachment’s clearance instructions and plan another suitable method for completing an end section that it cannot reach safely.
Q4. Can a Skid Steer Ditcher Make Sharp Corners?
Sharp corners generally require separate cuts and repositioning. Turning tightly with the boom engaged can bind the chain and bend the boom. Allow room for each cut’s lead-in and follow the attachment’s instructions for corners and curves.
Q5. Will a Trencher Automatically Maintain a Drainage Slope?
A conventional attachment does not automatically establish drainage grade. Set the planned elevations and check the bottom with suitable surveying equipment from a safe position. Ground contour and loader movement can change the working depth along the run.
