Measures and weights
Units of measurement in leather
Leather is a natural material and hence not available in rolls like other fabrics. For this reason, the external contours of the animal skin are too irregular. Leather is measured and calculated in square metres, decimetres, square feet (inch: inches), lengthwise or in kilogrammes. When speaking of leather, it is common to use words like weight leather and surface leather while leather laces and leather strips are sold by length.
Leather skin has different qualities within a skin making it impossible to sell the entire surface of the skin. These are sometimes cut in parts with different qualities and each section has corresponding technical terms.
Leather surface measurement
Large skins, such as bovine skins, are measured in square metres (m²). Occasionally, decimetres (dm²) are indicated. A cattle skin usually has 4.5 to 5.5 square metres. There are also larger (up to 6 sqm) and smaller skins. Leather dealers mostly sell complete and half skins. For certain purposes, further sections of the animal skin are sold. Smaller sections are sold reluctantly, leading to higher waste during the cutting process.
For large hides, the measure is usually square metres. However, decimetres are also given.
In the tannery, computerised systems measure the size of the skin at the end of the leather production.
Full hide - Half hide. The division takes place along the back line.
Lamb, pig and goatskin in the clothing sector are usually measured in square feet or square inches.
The conversion factor for the conversion from square metres to square feet is 10,764, from square metres to square inches 1550,003.
2,95 square metres x 10,764 = 31,75 square feet
45 square feet: 10,764 = 4,18 square metres
For leathers sold by surface, the tanner has a great interest in trying to get the largest possible surface during the tanning process.
Leather by weight
Heavy leather, such as sole leather, leather straps and bridle is calculated by weight. Also cutting waste is usually measured in kg.
Irrespective of whether a leather is sold by weight or area, the work steps in the tannery and the tanning process have an influence on the weight of a leather. In a comparison of chrome tanning, synthetic tanning and vegetable tanning, the area of tanned leather per 100 kilos of leather was measured. Chrome tanning was 18 m² per 100 kg, synthetic tanning 15 m² and vegetable tanning 13 m². With aircraft leather, the goal is that the leather is non-flammable and as light as possible.
Leather according to length
Reptile leather is calculated by length.
The leather thickness is measured in millimetres with special measuring instruments.
Measurement of leather thickness.
Leather can be over 6 mm thick.