BS EN ISO 17235:2015 pdf free.Leather — Physical and mechanical tests — Determination of softness.
BS EN ISO 17235 specifies a non-destructive method for determining the softness of leather. It is applicable to all non-rigid leathers, e.g. shoe upper leather, upholstery leather, leathergoods leather, and apparel leather.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 2418, Leather — Chemical, physical and mechanical and fastness tests — Sampling location ISO 2419. Leather — Physical and mechanical tests — Sample preparation and conditioning
3 Principle
A cylindrical rod of defined mass is lowered at a specified rate onto a securely clamped area of leather. The distension of the leather produced is recorded as the softness.
4 Apparatus
4.1 Test machine, shown in Figure 1. including the parts described in 411 to 417.
4.1.1 Circular aperture, A, diameter 35,0 mm ± 0,1 mm.
4.1.2 Metal rings, able to fit into aperture A and reduce the diameter of the aperture to
25,0 mm ± 0,1 mm and 20,0 mm ± 0,1 mm, respectively.
NOTE The apertures described above are more conveniently referred to by their nominal diameters of 35 mm, 25 mm, and 20 mm. respectively.
4.1.3 Clamps, B, capable of holding the leather securely both before the load pin is released and when the maximum force is applied while leaving the portion over the aperture free to move.
4.1.4 Cylindricalload pin, C, diameter4,9 mm ± 0,1 mm and length 11,5mm ± 0,1 mm rigidly attached to a cylindrical mass, 0. The total mass of load pin and cylindrical load shall be 530 g ± lOg.
4.1.5 Means of guiding the load pin, such that the load pin acts perpendicularly to the leather surface and the vertical travel of the load pin is restricted to a distance of 11,5 mm ± 0,1 mm.
5 Sampling and sample preparation
Condition the leather in accordance with ISO 2419.
NOTE
It is possible to take measurements without physically cutting a sample from the hide or skin.
6 Procedure
6.1 Select the aperture from 35 mm, 25 mm, or 20 mm.
NOTE  It is suggested that the apertures are used as follows:
一35 mm, measurement of firmer leathers, e.g. shoe upper leathers;
一25 mm, measurement ofleathers of, moderate softness, e.g. upholstery leathers and softer shoe upper leathers;
一20 mm, measurement of softer leathers, e.g apparel leathers.
6.2 Open the test machine and place the metal disc (4.2) on the upper face of the lower part of clamp B such that it covers the circular aperture.
6.3 Raise the load pin and close the test machine to clamp the metal disc in position.BS EN ISO 17235 pdf free download.