DESIGN AND CONSTRUCTION OF A PROTOTYPE OF AN ANALOG LEATHER SHRINGKAGE TEMPERATURE TESTER

Abstract

The leather tanning process is a process of converting organic material that easily rots into a stable material that is able to withstand biochemical attacks [1]. One of the important parameters in the leather tanning process is the shrinkage temperature. Skin shrinkage temperature is the temperature achieved when the skin shrinks a maximum of 0.3% of its initial length if the skin is heated slowly in a heating medium [2]. Currently, there are still many domestic industries who carry out tanning leather shrinkage temperature tests using manual methods, but this method is very inaccurate because it depends on operator observations. Apart from that, to find out the tanned process of the skin, you can also use a leather shrinkage test machine, such as the Gester leather shrinkage machine, GT-KC23 series. However, the price of this machine is quite expensive, so it is not applicable in the small and medium-scale leather processing industry. In this research, we will design a machine for measuring the shringkage temperature of tanned leather that is more practical and easier to use, and the test method will be standardized in accordance with the Indonesian National Standard (SNI) 06-7127-2005. The shringkage temperature measurement tool uses a PT-100 water temperature sensor, heater and a series of manual movement indicators. Data from the temperature sensor will be processed by the Arduino Uno microcontroller. This testing machine was tested on four types of leather, including vegetable leather, pickle leather, chamois leather, and aldehyde leather. Based on the results of testing tools on pickle leather, chamois leather, and aldehyde leather, it is also compared with the test results with the Leather Shrinkage machine, Gester brand GT-KC23 series, which is considered to be quite representative.