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 Tanning Process

Curing - As soon as the hide has been removed from the animal it must be protected from putrefactive bacteria. Curing is a method of short term preservation. This is achieved by either sprinkling it liberally on both sides with common salt, or by immersing it in a saturated brine solution.

Soaking - On arrival at the tannery the hides are soaked in water to remove the curing salt. This is most generally done in revolving processors holding anything from 100 to 200 hides in a load.

Liming - The hair and epidermis are removed by treating the hides in a solution of lime (calcium hydroxide) and sodium sulphide.

Tanning - Tanning involves combining the tanning agent and the hide protein to form a stable, durable, non-putrescible leather. After liming and fleshing (the removal of fat adhering to the back of the hide) the hide is split layer wise to produce a fine, smooth grain leather after tanning. The hides are then delimmed to remove all the alkalis from the liming process, this is followed by a weak enzymatic treatment called bating. This last named treatment makes the grain finer and smoother and gives the correct elasticity and plasticity in the finished leather. The final treatment before tanning makes the hide weakly acidic and is achieved either by pickling the hides in a weak acid and salt solution, or by a suitable pre-tanning process. The tanning process are of three main types, Chrome Tanning, Alum-tanning and vegetable tanning.

Chrome Tanning - This tannate is commonly carried out with the aid of basic chromium sulphate, a mineral salt which penetrates the hide very rapidly, tanning being complete in twenty-four hours. The leather is a pale duck-egg blue in colour, It is also known as wet-blue for its color derived from the chromium. More esoteric colors are possible using chrome tanning.

Alum-tanning is tanned using aluminum salts mixed with a variety of binders and protein sources. Very light shades of leather are possible using this process. This is the leather that most tanners refer to as wet-white leather due to its pale cream or white color. It is the main type of "chrome-free" leather.

Vegetable Tanning - In this case the hide is treated with vegetable tannins found in the bark and wood of certain trees. For centuries the bark of the oak tree was used as a source of tannin, but today a more common tannin is mimosa tannin found in the bark of various species of wattle tree. It is supple and brown in color, with the exact shade depending on the mix of chemicals and the color of the skin.

Retanning - Hides are now in the finishing stage of production. A wet drum process allows the addition of dyes, anti-mould chemicals, a re-tan agent, fat liquors to give the finished product a soft feel, and where necessary, flameproof chemicals

Drying - Hides are dried by first of all wringing excess water out in a large mangle, or setting machine, and then by stretching the hides on a frame which is then passed through a large heating chamber (Toggle). Then leathers are made thinner to their final thickness.

Pigmentation and Lacquering - Finished hides will have pigments applied to the surface. This is done using a combination or a roller coated for the initial application and a spray carousel to add subsequent coats of pigment. A top lacquer coat is applied to give the finish a layer of protection against wear and soiling.

Embossing – when necessary an embossed grain pattern is printed onto the leather's surface.

Drumming (Dry milling)- The hides are placed in side large stainless steel drums and tumbled. During this process the natural fibers start to loosen and a soft feel (or handle) is created.

Measurement - The leather is measured with an optic measuring devise. The measurement used is Sq.Ft

Then the very best leather, selected and quality inspected by our technicians before they hand cut each individual panel, Then the lining is carefully hand cut. The leather panels and lining are then passed on to one of our sewing specialists who begins the process of constructing the item using stitching that is 3 times stronger than required. Once the item is built the specialist then puts his name to it and hands it to our Quality Inspector for the inspection that every item must undergo before leaving the premises. Here at Leather Hub every garment is individual, a classic in its own right, each made by one highly skilled leather specialist.