Grappling and Clamping, plus More: The Mini Digger Power

11 September 2017

The anatomy of a mini-digger is typically illustrated by its compact outline and a 4-in-1 bucket outfitted with heavily reinforced steel plates, a shape and attachment that’s ideal for turning the vehicle on a button and digging trenches. It backfills and dump tons of dirt with raw muscular power, shadowing the scooping motion made by the human hand. Having made this boast, the human hand is capable of a great deal more than plain lifting. It can grab and pinch fragile objects. Two hands will quickly work in concert, maneuvering heftier items and switching effortlessly to fingertip control when handling finely sized materials and fabrics. Believe it or not, the same fluid motion is possible when hiring a mini-digger, a thought that opens the flexible lifting action of the excavator to the world of attachments.


Two or more curved sections of heavy-duty metal combine on a spring-loaded and hydraulically powered assembly to form a powerful grappling mechanism. The intention in this scenario is to engineer an operational mode where opposing forces close around an unwieldy mass, sealing it in order to make a lift. Typical working environments include a logging project where downed trees are cleared from a section of land, and debris is summarily escorted off of a construction project before commencing the building phase.

Alternate forms of mini-digger grapples include stone grapples and demolition variants, lifting mechanisms capable of adopting plated and multi-fingered configurations to optimize the holding force surrounding a particular class of item. Finally, modern engineering adds the power of the wrist as an optional feature to many of these grapples, incorporating a rotational component via hydraulic or pneumatic-generated power.

The Clam-shell Clamp

The primary function of this kind of attachment is to create a powerful seal between the two shell halves, thus forming an internal space where dirt or granular construction material can be lifted without leakage. The two shell sections use a vertical lifting trajectory, a motion shared by the grapple attachment we described in the above example. The aforementioned seal is gifted to the assembly by a cleverly integrated piston. When the piston is brought into action by some form of actuator assembly, it opens to release the volume of contained fine matter at its destination.

A hydraulic circuit typically combines with a clam-shell bucket to lift piles of rock upward and outward, perhaps stockpiling the loose matter on another floor of a rising building. It can also move bricks, pebbles, and bags of concrete with little effort.

Min-diggers shadow their larger cousins in every conceivable manner, a fact that extends to other forms of lifting besides digging holes. Of course, their compact footprint is going to place limitations on the quantities of matter that can be grappled and clamped, so read the product documentation before attempting to lift that oversized tree trunk.