The upper is turned up internally and bonded to the insole by thermal adhesive and stapling. Then the sole is glued and pressed onto the suitably prepared insole. The shoe is built on a mould that determines its fit characteristics. Models with this type of construction are particularly robust, and may have various degrees of flexion and torsion, depending on the insole used.
This is a manual process in which the upper is sewn onto a soft insole so as to form a sort of bag into which the mould is inserted. A band sewn around the profile of the insole is then turned over a wedge. This process guarantees the shoe extraordinary flexibility and, at the same time, softness and lightness.
TUBULAR CONSTRUCTION (HAND SEWING)
Footwear produced with this type of technique is essentially composed of a band that wraps around the foot from below, leaving only the uppermost part uncovered. This part is then covered by a toebox, generally hand-sewn, with the stitching left visible. Thanks to the flexibility guaranteed by this particular assembly, the resulting footwear’s main strength is its comfort, making it forever in demand, and highly appreciated for all wearer ages.
SLIP LASTING CONSTRUCTION
Although similar to the tubular construction, this method attaches the leather upper separately from the
lining, which is built like a glove over the mould of the shoe, forming a closed bag for the foot. The method
is also sometimes called the ‘Bologna Technique’, and eliminates the need for an insole, guaranteeing
greater softness for the shoe.
Hand sewing requires highly skilled workmanship to bond the upper, the insole and the sole together by means of a hand-stitched seam, using a special needle and single thread, i.e. without any join. The visible seam creates a distinctive look, requiring an exceptionally high level of skill to guarantee uniformity. Hand sewing means that each and every pair of shoes is extraordinarily unique.
MECVAL (MACHINE SEWING)
A technique in which the upper is first fixed to the sole by means of several glue points, in order to give greater stability to the two parts during subsequent processing. Then, the upper and the sole are sewn together by a Mecval machine, which makes them inseparable.
The advantage of Mecval processing is greater flexibility for the shoe.
STROBEL COMFORT CONSTRUCTION
This technique is widely used in the construction of light footwear that needs to guarantee bending and torsion. The upper is paired with a lightweight insole forming a sock that is then bonded to the sole. The Strobel construction allows the weight of the shoe to be kept to a minimum, and is therefore ideal for shoes designed for comfort and relaxation.
The upper is bonded to the insole, which is carded on the edge, and assembled on an aluminium mould. Adhesive is applied to the lower part of the edge of the upper, and the rubber sole and heel are moulded and vulcanized directly under the shoe, before being cooled to form a single body.
The uppers and insole are prepared in the same way as for vulcanization. The moulds of the bottom, once sealed tightly to the shoe, are then injected with a plastic material, usually PVC or polyurethane, and left closed until the bottom solidifies completely and the shoe is extracted.