Terra Innovation Centre

Work BootConstruction Methods

Terra boots employ several construction methods. Learn how this process creates the most advanced work boots in the world.

When the upper is completed it is pulled over a last, a foot form which determines the shape of the boot, by a lasting machine and tacked in place.

The upper is heated and left to cure on the last before the sole is attached. This time allows the upper to take the shape of the last, providing a structured and engineered fit, defining the final shape of the boot.

Developing lasts for safety footwear include the added complication of shaping around a safety toe cap. The shape of the boot needs to be designed wider to accommodate the toe cap, but maintain a proper anatomical shape to fit the foot securely enough to be safe and supportive.

The Footbed
1 Upper Pulled onto Last

Upper Pulled onto Last

2 Heated and Cured on Last

Heated and Cured on Last

3 Sole is cemented in place

Sole is cemented in place

4 Boot is laced and finished

Boot is laced and finished

Terra boots commonly employ two construction methods: Direct Inject and Cement construction.

Direct Inject

A lightweight liquid soling material is injected in two densities onto the lasted upper of the boot. A higher density material is injected first to create a tough durable outsole. In the case of TPU and various rubber compounds, this layer may be exceptionally thin, but still remain very durable. The process can be compared to the outer skin of performance tires. The material sports a hard shell which is highly resistant to abrasion and wear. The midsole is then injected at a lower density to create a lightweight inner core, providing a cushioned shock absorbing layer. This process creates a permanent waterproof seal between the upper and the sole that is extremely durable and flexible. By removing stitching from the bonding process, TERRA dual density injected boots provide much higher water resistance in addition to excellent comfort and flexibility.

Cemented

The upper, midsole and outsole layers are cemented together with an adhesive compound, adhering the layers and creating a tight seal. The result is a lightweight, flexible boot or shoe, ideal for many environments. Cemented outsoles often employ light-weight EVA midsoles and are commonly used on athletic or oxford style footwear, as well as hikers.

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