When paired with an attachment, a compact excavator becomes a versatile tool carrier that can work in additional applications, handle tasks normally completed by a separate machine and even possibly be the only machine needed on a particular jobsite," says Tom Connor, excavator product specialist with Bobcat Company.
Similar to their cousin, the skid-steer loader, compact excavators are ideal for fitting into small spaces and powering attachments. Unlike skid steers, compact excavators have the added ability to allow the attachment 360-degree access around the machine.
Add an attachment, add productivity
With a quick switch between attachments, your rental customers can break concrete, load the remains into a truck and grade the cleared site - all with the same machine.
With an attachment or two, compact excavators can stay busy on a jobsite all day. "Thinking outside of the box can improve your equipment utilization," says Brian Rabe, compact excavator product manager with Gehl Company. "Most people think of excavators only for digging applications. Their value in other non-digging applications like demolition, landscaping, land clearing and material lift/place/remove applications can add to your bottom line."
While it seems compact excavators and attachments are an ideal pair, keep in mind the boundaries these machines have. There might be a tendency by some rental customers - both contractors and homeowners - to push the limit on attachments because it pushes the utilization of the machine. But pushing the limits can create a situation where these smaller carriers are asked to do too much.
While you want to make the best use of available power, you need to do so within the confines of the machine's specifications to prevent overloading, which can cause overheating and excessive and premature wear, as well as compromise stability.
Determining lift capacity
Your rental customers need to understand that lift capacity of a compact excavator will decrease as the boom extends. If you're operating close to the machine, lift capacity will be greater, for instance. As you extend the arm out to the side and up, the ability of the load to tip the machine will be greater.
On many attachments, the lift capacity of the machine will affect the maximum weight of an attachment that the excavator can use, says Connor.
"For some attachments, such as the clamp or grapple, the lift capacity of the excavator will limit the weight of the material that can be picked up and placed with the machine," he explains. "For example, on a landscaping jobsite where an excavator is being used to place boulders, the weight of a boulder will be limited by the lift capacity of the machine."
So, how much can your compact excavator lift? Some manufacturers print lifting limits on decals affixed directly to the machine. You can also find them printed in most product literature and owner's manuals.
"The key is the values on the lift capacity charts assume the standard bucket is being used," says Connor. "For attachments other than the standard bucket, calculations must be made to reflect a particular attachment in question. A compact excavator will have rated lift capacities for various configurations of the machine, and the lift capacities should be noted to customers and only approved attachments should be rented with the machine."
Optimizing hydraulic flow
A compact excavator is a hydraulically driven machine, as compared to a backhoe-loader, which is horsepower driven. You'll want to ensure that the engine in your machine has enough horsepower to adequately power the hydraulic pump.
"The horsepower of the machine will indicate the machine's ability to produce and sustain adequate hydraulic performance of an attachment - the ability to provide flow (GPM) and pressure (PSI)," explains Connor.
Engine horsepower is an important part of the performance equation, but more horsepower does not necessarily mean more hydraulic performance for the attachments, notes Rabe.