How to Convert a STIHL Into a GeoTrencher

February 27, 2026

How to Convert a STIHL TS420 or TS500i Into a GeoTrencher

Contractors across Australia are converting their STIHL demo saws into precision trenching systems using the GeoTrencher attachment. Instead of investing in a dedicated mini trencher, many professionals are upgrading equipment they already own.

If you already have a TS420, TS500i, TS700 or TS800, converting it into a GeoTrencher system is a practical and cost-effective solution for narrow trenching applications.

Compatible STIHL Models

The GeoTrencher attachment is compatible with the following STIHL demo saw models:

STIHL TS420
STIHL TS500i
STIHL TS700
STIHL TS800
STIHL TS710i
STIHL TS910i

These models provide the ideal power and drive configuration required for precision chain trenching.

Why Convert a STIHL Demo Saw?

Cost Efficiency

There’s no need to purchase a dedicated mini trencher. Converting your existing demo saw allows you to maximise equipment you already own.

Compact Access

The GeoTrencher system is ideal for tight residential access areas where larger trenching machines cannot operate efficiently.

Cleaner, Narrow Trenches

Perfect for:

Irrigation systems
Electrical conduit
Landscape lighting
Strip drainage
Fibre and cable installation

Reduced Ground Disturbance

Chain trenching creates narrow, defined cuts, meaning less mess and minimal landscape repair after installation.

Installation Overview

The conversion process is straightforward when following the correct installation steps:

Remove the water attachment from the STIHL saw.
Relax and remove the belt.
Remove the blade assembly.
Install the GeoTrencher drive assembly.
Correctly tension the belt using the STIHL tool.
Fit the trenching bar and chain (ensure the chain teeth face forward on the top edge).
Tension the chain correctly.
Install and secure the safety bar.

Following the correct belt and chain tension procedure is essential for optimal performance and longevity.

Download Installation Guides

For full illustrated instructions, download the appropriate guide below:

Download STIHL TS420 / TS500i Installation Guide
(Click here)

Download STIHL TS700 / TS800 / TS710i / TS910i Installation Guide
(Click here)

Common Mistakes to Avoid

Installing the chain in the wrong direction
Not properly tensioning the belt
Over-tightening the chain
Failing to secure the safety bar

Taking the time to correctly tension and secure all components ensures smooth operation and long service life.

Ready to Convert Your STIHL Saw?

View the GeoTrencher attachment here and turn your demo saw into a powerful precision trenching system.
STIHL GEOTRENCHER PRODUCT HERE