An inexperienced trencher operator can cause costly mistakes.
From start to finish, educate yourself on the task at hand—know your digging conditions, recognize potential safety hazards and understand the relationship between your trencher attachment and prime mover.
With this knowledge, you’ll be able to operate your trencher attachment like a pro, saving time and money.
“It’s important to be familiar with and know the controls and adjustments on both your trencher attachment and prime mover,” says Dave Aldrich, Light Construction Dealer Development and Service Manager for Paladin Attachments, which includes Bradco trencher attachments. “Take time to learn how they operate now. Such knowledge is crucial for safe, efficient operation of your equipment.”
Before you begin
Safety stop: Inspect your job site and take notice of any potential hazards in the area. Trenching through a hidden utility line could cause electrocution and death. Call all utility companies and have them plot out all of their lines before operating your trencher attachment or dial 811 before you dig.
Prior to starting a trench, it is always a good idea to plan out your job. Several variables need to be taken into account before trenching:
- Trench requirements
- Potential safety hazards
- Digging conditions
- Trencher tooth pattern
- Digging chain tension
Before your trencher touches the dirt, match the tooth type and pattern with your soil type. Talk with your dealer or manufacturer representative about the soil type you will be digging into. Then choose the proper teeth for your application:
- Cup – The most common teeth chosen for trencher attachments. Ideal for good digging applications like black dirt, loam, moist clay, sand and sandy clay.
- Shark – Ideal for rocky, abrasive or compact conditions like caliche.
- Frost – Ideal for the most extreme trenching applications like coral, frozen ground and fracturable rock.
In order for your trencher attachment to be successful in these applications, you will also have to take into account your prime mover’s hydraulic horsepower capabilities and the depth you will be trenching. Trencher attachments do have their limitations, so match not only your trencher teeth to your digging conditions, but also the machine’s hydraulic capabilities and your trench depth.
When trenching, it is important to have your trencher chain properly adjusted. You do not want the chain too loose or too tight depending on the style of boom and tensioning system you are using. Follow the manufacturer’s instructions in your operator’s manual for proper adjustment.
Safety stop: Never work on or make adjustments to any part of your trencher attachment while the unit is running. You could get caught in the chain or digging teeth, which could cause severe injury or death.
Starting & stopping your trencher
Power is supplied to most trencher attachments by the prime mover’s auxiliary hydraulic system. In this case, the trencher itself does not have an on/off switch, but is operated by the prime mover’s auxiliary hydraulic control mechanism. To start your trencher, engage the auxiliary hydraulics. To stop your trencher, disengage.
Trencher speed and power are determined by the flow coming out of the auxiliary system, which is dependent on the prime mover’s engine speed. To increase trencher speed, increase the prime mover’s engine speed. To slow down your trencher, decrease the prime mover’s engine speed.
Time to trench
When first starting a trench, set the prime mover’s engine to half throttle. This will reduce the shock to the prime mover and trencher attachment when the digging teeth first contact the ground. Position your prime mover with the trencher boom directly over the center of where you will dig your trench. It will take about four feet of trenching before the trencher will be able to operate at the desired depth, so plan for this and position the trencher about four feet behind where you want the actual trench to start. Once the trench is started, set the engine back to full throttle.
Slowly lower the trencher arm into the ground to start the trench by lowering the trencher attachment with the loader arms and loader bucket controls. Carefully creep backwards as you roll the trencher boom down into the soil with the bucket and lift arms of the loader. Watch the crumber end so it does not get caught up on the trencher and continue to creep backwards. Once you have reached your required depth, you should be at a 60- to 65-degree angle with the trencher boom. A 48-inch boom will give you 48 inches of digging depth at a 65-degree angle.
Safety stop: Look behind you before reversing your prime mover to trench. Be aware of any person or obstruction in its path and observe any terrain changes such as drop-offs or soft ground.
When trenching, remember to keep the discharge auger running about an inch off the ground; typically the skid shoe on the right-hand side of the machine will keep the auger at that height. This will keep the dirt pushed back away from the edge of the trench to help eliminate the spoil from falling back into the trench and prevent cave-ins.
Avoid a wrong turn
Turning your prime mover is easy. Add a trencher attachment to the mix and you have to be a little more cautious. Avoid making turns with your trencher attachment. A gradual turn or radius can be done, but you will put side loads on your trencher boom, causing excessive chain wear and possible damage to the boom and trencher assembly. Turning too tightly while trenching will cause the trencher boom to bend and jam in the trench and stall, leading to excessive oil temperatures. Be cautious at all times when turning. To make sharp turns and 90-degree angles you will need to dig two trenches.
Completing your trench
Once you’ve dug your trench, remember that the trencher boom is at an angle and that you must continue trenching until the end of the boom has dug past the proposed end of the trench. Once the end of the trench has been dug, keep the trencher running and raise the loader arms to lift the unit clear of the trench. When the trencher has cleared the trench, disengage the auxiliary hydraulics to stop the trencher and then drive the prime mover away from the trench.
Safety stop: Keep equipment away from the trench after it has been dug so the weight of the unit does not cause a cave-in.
“Remember, your trencher attachment’s performance is directly related to the power available from your prime mover’s auxiliary hydraulic system,” Aldrich says. “If the trencher seems to lack power or speed, it may be due to a lack of sufficient auxiliary power. Be sure to match the size of your trencher attachment with the hydraulic capabilities of your machine.”
Trencher performance is also related to how well it is maintained, digging tooth wear and type and size of digging chain, crumber boom and shoe used. Consult your operator’s manual for maintenance tips or ask your local dealer. At the end of the day, taking the time to operate and maintain your trencher attachment correctly will save you time on the job and put money back in your pocket.
EDITOR’S NOTE: This article was written by John Thomas. Thomas is the vice president of marketing and business development for Paladin Attachments, which includes Bradco Attachments, based in Dexter, Michigan.