An excavator arm is more than the connection between the boom and bucket. It’s an important component for reach, digging depth, breakout force and lifting capacity. With many core concepts to consider, it’s essential to select an arm that aligns with your project requirements. Choosing the wrong one may lead to project inefficiencies and a potential loss of revenue.
We compiled this comparison guide to help you make an informed decision based on your project needs.
With various types available, understanding how to choose excavator arms is critical to ensure your project’s efficiency, productivity and safety. Selecting the wrong one may result in reduced productivity and efficiency, as your excavator will be unable to complete its specific job. This can ultimately result in lost revenue.
So, the right excavator arm means using the right equipment for the right job. But it also means you’ll have to balance three key elements — the arm’s reach, power and application. In addition to those, you’ll want to consider the following factors:
While there is much to consider, we can simplify the excavator arm selection process by mainly focusing on arm type and application.
Just as there are different types and sizes of excavators, there are also various types of excavator arms with different reaches. While numerous configurations exist, we’ll cover the four common types.
Short arms are made for maximum digging power and lifting capacity, and not necessarily for reach. They’re typically used on compact excavators and heavy-duty machines that prioritize breakout force and stability. Short arms are thick and reinforced, and have a higher hydraulic pressure capacity.
They’re used in applications such as heavy material excavations, foundation digging and loading at close ranges. Short arms are perfect for projects that demand high breakout forces and tight-space maneuvering.
Using short-arm excavators provides the following advantages:
The standard arm is the most common excavator arm setup, consisting of a single boom and a stick attached to a bucket. You may also know this as a “mono boom.”
Its balanced structure provides a moderate reach and digging depth, making it an excellent choice for general excavation, trenching, grading and loading. Standard arms are your general-purpose go-to for construction and earthmoving tasks. They are:
Long-reach arms are designed to extend your capabilities in more challenging environments. They have an extended and reinforced boom and stick, which helps you achieve a greater horizontal reach and depth.
Long-reach arms are indispensable for applications such as dredging and deep excavations. You can also use them for riverbank, pond or canal work, as well as slope finishing and grading. They’re a must-have for projects requiring long-distance digging or where the excavator cannot be positioned close to the work area.
Their advantages include:
Extendable arms are hydraulically powered with a telescoping inner section. This design allows them to extend or retract to change their reach dynamically. They’re the perfect balance between standard and long-reach arms.
Extendable arms can be used for basement excavations, below-grade work and truck loading. If you have projects that require deep vertical extraction or variable reach, extendable arms are a great choice. They have:
To make an informed decision, you should also understand the interplay between excavator arm reach specifications and their power. We’ll discuss this trade-off with a short-arm vs. long-arm excavator comparison.
Short arms have a shorter horizontal reach and digging depth, which requires more machine repositioning, especially in wider or deeper areas. Long arms have a much greater horizontal and vertical reach, without repositioning. They can access areas a short arm can’t, but that reach comes at the cost of strength and control.
Thanks to the short arms’ design, their force is applied over a shorter distance, which gives them more power for tough materials. They’re best matched with dense soil, clay, rock and quarry work.
Long arms have a lower breakout force. Their longer design reduces their hydraulic leverage. Since they have less power, they’re best matched with loose soil, sand, grading and slope work.
Because the load is closer to the machine’s center of gravity, short-arm excavators have a greater lifting power. Long arms’ design reduces the lifting capacity of an excavator. The increased leverage from an extended arm reduces their lifting power.
When precision and control are a priority, consider a shorter arm. Short-arm excavators offer greater control and accuracy, especially in tight areas or detailed work. They’re better for trenching, foundation digging or lifting near the machine. Longer arms, on the other hand, struggle to maintain their precision, particularly at their maximum reach.
Compared to shorter arms, long-arm excavators have less stability. Their design shifts the center of gravity further from the excavator’s base. This increases the risk of tipping if loads are too heavy or the arm is extended too far. Long arms will require additional counterweights for better balance. Short arms are more stable due to the reduced leverage effect.
We can summarize the above points with a general rule of thumb. Short arms equal more power, but less reach. Long arms equal more reach, but less power. Standard arms are a general-purpose compromise between the two. That said, it all depends on its application.
Here are a few examples where the arm is matched to its primary application, to help you with your selection.
Long-reach excavator arms are a must when you need an extended reach and smooth control over breakout force. Industries include:
If you need brute strength, short arms are the best choice. They shine in scenarios that need more digging power with precision. Industries include:
Extendable arms’ flexible reach without the need to reposition makes them ideal for tight spaces that need better control. Industries include:
The standard arm is an all-around performer for everyday excavation, grading and loading. Industries include:
Ultimately, the right arm primarily depends on its application. Whether you need an excavator for mass excavation, trenching or demolition, Gregory Poole has the right one for you.
We offer various equipment, including genuine Cat® excavator models and other quality manufacturing brands, like Bobcat. With Bobcat excavators, you can use various arm configurations, such as the Pro Clamp™ System and Hydraulic X-Change™, to optimize them for various tasks.
With over 70 years of experience, we can also help you find the ideal heavy equipment for your project’s specific needs. Contact us online today to speak with a sales rep or product support specialist for a personalized consultation.
