How a Bespoke Shoe Is Made (4): Insole and Toe/Heel Stiffeners

The Insole

To permanently attach the upper – which has been pulled over the last – an insole is required. It forms the inner base of the shoe and connects the upper to the other components of the shoe bottom using stitches, nails, or glue, depending on the desired construction and type of shoe.

Its shape is defined by the underside of the last. To create it, a piece of high-quality sole leather – preferably oak bark–tanned using the traditional pit tanning process – is placed on the last bottom and cut by hand with a knife until it fits precisely along the last’s edge. The thickness of the insole depends on the construction method and the shoe’s intended use – as well as whether a custom footbed is included in the final shoe or the customer walks directly on the insole.

Depending on the chosen construction – for example, in welted shoes (more on that later) – the insole must be prepared accordingly, in a process known as "channeling." This involves cutting a narrow groove, or feather edge, into the insole, where the stitching will later run. This labor-intensive step is done entirely by hand using a sharp knife and special tools, such as an insole plane.

Toe and Heel Stiffeners

Before the shaping process of lasting can begin, the toe and heel stiffeners are inserted between the outer and lining leathers of the upper. These stiffeners reinforce specific areas of the shoe where the foot needs extra support or the shoe requires enhanced structural stability – primarily at the toe and heel.

The edges of the stiffeners are always thinned out before insertion to ensure smooth transitions and avoid pressure points. Heel stiffeners, also called heel counters, are traditionally made from vegetable-tanned leather, as it absorbs moisture and enhances wearing comfort. The same principle applies to toe stiffeners. However, for reasons of durability, shape retention, and weight reduction, toe stiffeners are now sometimes made from synthetic materials.

These components are complemented by a reinforcing leather strip – also known as a side lining – which connects the toe and heel stiffeners and enhances the shoe’s structural integrity by minimizing any visible transition between the two.

In the next Journal article, we’ll focus on the lasting process – where the upper is pulled over the last and given its final shape.