Detachable Shims

In the world of earthmoving and construction, precision is often the difference between a high-performing machine and a costly repair bill. When connecting attachments—such as buckets, auger drives or hydraulic breakers—to an excavator or skid steer, the fit must be exceptionally tight. Even a few millimetres of "slop" or lateral movement can lead to accelerated wear on pins and bushings, reduced breakout force, and potentially dangerous instability. To combat this, shims are used to fill any excess space. While standard shims have been the industry baseline, detachable shims represent a new and modern way to maintain efficiency.

What are Detachable Shims?

Detachable shims are specialised spacers designed to be installed and removed without requiring the full disassembly of the connection point. Unlike traditional circular shims that must be slid over a pin during the initial mounting process, detachable shims often feature a "U-shaped" or slotted design. This allows them to be slipped into the gap between the attachment ear and the machine hitch or dipper arm while the pin is still partially or fully in place.

What are Shims used for?

The primary use of a shim is to eliminate lateral movement (side-to-side play). When an attachment is manufactured, there is always a slight tolerance gap to ensure it can actually fit onto the hitch. Over hours of operation, constant friction and the high torque of hydraulic work these moving surfaces do wear down, widening the gap.

Removing the need to disassemble your hitch and disconnecting the attachment, Detachable shims are particularly useful in:

• Field Repairs: If an operator notices excessive rattling during a job, a detachable shim can be hammered into place and secured quickly, avoiding the need to take the machine to a workshop for a full pin extraction.

• Multi-Machine Compatibility: Detachable shims allow for a "modular" fit, letting one attachment work across different machines with varying tolerances.

• Precision Levelling: In specialised alignment systems like Inclinometers, Laser Receivers, 3D Grade Control and Global Navigation Satellite System, or Digga's 'HALO' Auger Alignment System, maintaining zero-play is critical for the sensors to provide accurate feedback. Detachable shims allow for fine-tuning that can be adjusted as the metal settles.

Comparison: Detachable vs. Standard Shims

What's the difference between Standard shims and Detachable shims? 

Standard shims are essentially large, hardened steel washers. Because they are a closed circle, they provide the most robust surface area for the pin to rotate against. However, if you need an extra 2mm shim installed after you’ve already hammered in your pin, you have to undo all that work, extending the time the machine is inoperable. 

Detachable shims solve this "hindsight" problem. While they are sometimes viewed as less permanent, the use of a simple cable tie fix the shim into place to ensure they don't vibrate out during heavy vibration (such as when using a rock breaker). The use of Detachable Shims may not be forever, but they will allow the operator to complete the job and considerably reduce downtime and gaps in earning.

In summary, while standard shims are the choice for a permanent workshop rebuild, detachable shims are the indispensable tool for the active operator. They provide a practical, time-saving solution to keep attachments tight, protecting the longevity of the machine's most critical pivot points.