How leathers are made – video
Leather is one of the earliest crafts that accompanied humans since the origin of the species, it is a durable, versatile and a natural material. Something of high value accomplishing a whole range of uses. We appreciate the look, feel and even unique smell of leather but a question may arise how is modern leather made. We aim to add light to this by means of this concise video as we highlight the various key processes in making leathers the hides from large animals and skins from small animals come from many parts of the world and are a byproduct of their meat industry.
Hides arrive at the tannery after being treated with salt to preserve them from bacterial action the first process performed is to shake out the salt avoiding pollution of the water system. The leathers are then soaked in lime in a process called blaming this chemically dissolves the hair removes unwanted proteins and opens up the fiber structure this process swells the leather considerably. Remembering that this material comes from an animal it still has fleshy parts to it therefore the next process is fleshing. The fleshing machine has many cutting blades and a revolving cylinder that cuts away unwanted fleshy matter and regularizes leather thickness. The leathers pass on to the next stage called trimming where workers cut away useless or unwanted material from the edges of raw hides to give them a better shape.
Next is a very important operation that takes place called splitting as the leather is still of a thick dimension this is the operation of cutting a hide or skin horizontally into two layers the upper layer the more external part of the animal is called top grain and the lower layer is called split. Now the tanning process takes place in this case the hides are placed inside a wooden rotating drum specially designed for tanning. Tanning agents convert the raw fibers of the hide into a durable product preserving it, improving its abrasion resistance and heat and flex resistance and able to endure repeated cycles of wetting and drying. Next two large rolls squeeze out the excess moisture as the hides are fed through a machine this is termed ringing the leathers are called wet load and may now be selected or graded as desired according to the destination of use. Once they have been selected they need to be reduced and made uniform in thickness this is done by a shaving method normally a machine with a rapidly revolving bladed cylinder the leathers are then returned and dyed. Through a further tanning treatment to modify the leathers properties the leathers an hour uniformly dyed.
How leathers are made
The natural beauty of leather is made even more striking by the wide variety of shades which the modern Tanner is capable of producing. The last of the wet operations is the fat licker ring to grant leather permanent softness, elasticity and flexing resistance. Now we come to the drying operations the first step is setting out our working over the grain surface to remove excess water and eliminate wrinkles. Leather drawing can be continued by various methods one of these is vacuum drying where leathers are put on a large hot flat plate and another plate presses down and sucks the water out of the leather by creating a vacuum. This is a very effective method there the toggling leathers are fixed on frames with toggles or clamps. The leathers then go through a dryer this stretching can be done manually here is a machine does it automatically. Another method is suspension drawing the hides are suspended from the ground on a wire or chain so that air has free access to both sides and move high up around the tannery complex. In this way the leathers dry at room temperature. Leather is staked to make it open and softer, pins pound the leather from both above and below hundreds of times as it passes through the machine stretching and flexing the leather in every direction this softens a leather remarkably. Some skins have natural healed scratches or parasitic damage in the grain of the leather a very special flexible paste stucco can fill in such gaps. A light buffing or sanding leaves a clean smooth surface ready for the subsequent finishing operation.
The finishing Department is the area where an alert and creative mind adds the final touches to enhance the natural beauty of leather. One method of applying the finish is the rotary spray several spray guns are mounted on a unit which continuously revolves over the leather unique patterns and two-tone effects can be obtained. Once the leather is dry an artificial grain pattern is often created by embossing the leather using edge or engraved rolls. Grain pattern and softness can be further enhanced by joy milling the leather before being delivered to the customer. The leather is measured by a very precise machine. A completely different system of finishing or enhancing leather usually with split or heavily buff leather, maintaining the same thickness and softness. The technique consists of creating the finishing film on a continual support of release paper, an adhesive is applied to the film then the film is pressed on the leather. The finished leather is then removed from the release paper displaying a perfectly uniform surface. In viewing these principle processes you can appreciate the passion, dedication, technology and creativity that goes into working and finishing leather.