Shoe making is a labor-intensive process, and the cost of producing the many components of the shoe reflect the skilled labor necessary. Each phase of production requires precision and skills, and taking short cuts to reduce costs can result in an inferior shoe. Some shoes[shoes?:shoes paper pattern cutter] have no insole[insole?:fibreboard insole pattern cutting machine] board. Instead, the single-layer upper is wrapped around both the top and the bottom portions of the foot. Most shoes, however, consist of an insole board that is cemented to the upper with cement.
1.Shipping and stamping the fabric, prepared rolls of synthetic material and rolls of dyed, split, and suede leather (used as part of the foxing) are sent to the factory.
2 Next, die machines stamp the shoe shapes, which are then cut out in cookie cutter fashion with various markings to guide the rest of the assembly. After being bundled and labeled, these pieces are sent to another part of the factory where they'll be stitched.Completed running shoes are quality tested using procedures developed by the Shoe and Allied Trades Research Association. Defects that are checked for include poor lasting, incomplete cement bonding, and stitching errors.
3.Assembling the upper and the insole, the pieces that will form the upper part of the shoe are stitched or cemented together and the lace holes punched out. These pieces include the featherline, the vamp, the mudguard, the throat (with eyestay and lacing section), the tongue, reinforcements such as the saddle or arch bandage, the collar (with Achilles tendon protector), the foxing, and the logo. At this point, the upper looks not like a shoe but like a round hat, because there is extra material—called the lasting margin —that will be folded underneath the shoe when it gets cemented to the sole.
4 Next, the insole is stitched to the sides of the upper. Stiffening agents are then added to the heel region and toe box, and an insole board is inserted.
5.Attaching the upper and bottom parts, the completed upper is heated and fitted around a last, a plastic[plastic?:Plastic sample cutting machine] mold that forms the final shape of the shoe. An automatic lasting machine then pulls the upper down over the last. Finally, a cement nozzle applies cement between the upper and insole board, and the machine presses the two pieces together to bond them. The upper now has the exact shape of the finished shoe.
6 Pre-stamped and cutout forms of the midsole and outsole or wedge are layered and cemented to the upper. First, the outsole and midsole are aligned and bonded together. Next, the outsole and midsole are aligned with the upper and placed over a heater to reactivate the cement. As the cement cools, the upper and bottom are joined.
7 The shoe is removed from the last and inspected. Any excess cement is scraped off.
