Abstract: A triaxial forces sensor was designed to dynamically measure a cutting force, a feeding force and a lateral force of a working saw-chain in real-time. The effects of chip mounting on sensitivity and nonlinearity in the tested forceorientation was analysed. The across sensitivity was discussed in the across tested force-orientation. The across sensitivity was from 3.2 x 10-6N-1 down to 4.27 x 10-7N-1 and the nonlinearity of feeding force was from 7.8%down to 0. 025%, after the chip mounting of the feeding force was adjusted. The test system’ s sensitivity of cutting force, feeding force, lateral force was 5.51 x 10-6N-1, 6.45 x 10-6N-1 and 4.05 x 10-6N-1, respectively.