A new generation SG300 substance gauge has been developed by MSA Engineering in conjunction with BLC. The unit is light (weighing 1.3kg compared with 1.8kg of the previous design) and comprises a specified anvil arrangement and spring force so that it more closely conforms to ISO 2589:2002. The SG300 can be calibrated through a screw-adjustable, constant force, spring mechanism. This allows it to be adjusted, if required, using an electronic load cell to factory parameters conforming to ISO 2589:2002.
It is designed to be held in one hand (either left or right) leaving the other hand free to insert the material to be checked into the gauge. Additionally, the base of the frame has been designed to allow the gauge to be used on a bench (with an optional clamp) or to stand upright when not in use. Due to the shape of the new SG300, the dial is in the line of sight of the operator. Consequently, it gives the optimum reading position and can be read without tilting the instrument and without danger of error due to parallax.
The SG300 has been designed to be as close as possible to the ISO standard. It is important, therefore, to demonstrate the comparability between ISO 2589:2002 and the SG300. ISO 2589:2002 is based on IUP 4 of the International Union of Leather Technologists and Chemists Societies (IULTCS). This is intended for the measurement of all leather types. ISO 2589:2002 describes a dial micrometer type gauge which is dead weight loaded, the spring force equivalent to 500gf/cm2. The presser foot is flat, circular and of diameter 10mm, and its direction of movement is normal to the face of the anvil. The anvil is the flat horizontal surface of a cylinder also of diameter 10mm. The analogue dial is graduated to read from 0.1mm.
