Magda Kubuśka-Orłowska

The aim of the present study was to determine the effects of initial chain tension and feed force on the wear rate of chipper chain cutters in gasoline-powered chainsaws. Wear was assessed by measuring the tip radius as cutter dulling has a considerable influence on chainsaw performance. Tests were carried out for three feed force values: 15 N, 35 N, and 70 N, and for two initial tension settings—a tight chain and a slack chain. The tests also measured cutting efficiency per unit of kerf area. The experiments involved pine wood and were conducted on a specially designed test rig that maintained a constant feed force. The tip radius was determined by means of a microscope and computer image analysis software. Wear intensity over time was evaluated using the dulling coefficient. The results showed that the applied initial chain tension and feed force significantly affected the cutter wear rate, which was significantly higher at lower feed force values. The wear rate was also increased by lower initial chain tension, which can be explained by greater cutter deflection from the kerf plane.

The aim of this study was to determine the influence of initial chain tension, feed force, and wood hardness on the variability of the cutter’s deflection angle during petrol chainsaw operation. Cutting wood with a chainsaw is a complex process that has not been fully elucidated to date. During operation, the position of cutters with respect to the workpiece may vary. The situation is additionally complicated by the fact that chainsaws are powered by one-cylinder gasoline engines characterized by highly variable instantaneous rotational speeds. The experiments involved two types of wood (pine and oak), two initial tension values (tight vs. slack chain), and two feed forces (20 N and 80 N). The cutting process was recorded with a high-speed camera at 12,000 fps to determine cutter deflection angles, instantaneous speeds, and accelerations for all the aforementioned cases. It was found that at the lower feed force the cutter deflection differed depending on the initial chain tension, and a greater cutter deflection angle was observed in pine wood processing. It was also found that speed and acceleration in the Y axis were much lower than in the X axis. Additionally, the rear part of the cutter revealed greater speed variation in the X axis.