Design and Fabrication of a Strain Gauge Type 3-axis Milling Tool Dynamometer

This paper presents the design and development of low cost strain gauge type milling tool dynamometer, which is suitable for measuring milling forces. The designed dynamometer contains four octagonal ring members on which strain gauges were bonded. The strain induced on the strain gauges due to milling forces during cutting was measured in terms of voltages using a Wheatstone bridge. A data acquisition system was connected to the dynamometer to acquire the data. The end milling operation was carried out on AISI 1020 steel work pieces of 60 mm x 30mm x 20 mm size using different combination of cutting parameters designed by design of experiments Taguchi approach on CNC milling machine. Machining tests were performed at different cutting parameters and measured cutting forces were compared with those measures by Kistler Dynamometer. The results showed that the dynamometer could be used reliably.