The influences of circular saws with sawteeth of mic-zero-degree radial clearance angles on surface roughness in wood rip sawing

作者：Li, Weiguang^*; Zhang, Zhankuan; Peng, Xiaorui; Li, Bo

来源：Annals of Forest Science, 2017, 74(2): 37.

DOI：10.1007/s13595-017-0632-3

• Surface roughness
• Sawtooth
• Radial clearance angl
• Wood sawing
• Side edge

Key message The sawtooth parameters of the side edges likely affect surface roughness to a large extent in wood sawing. Our results point out the need to optimize the parameters of the side edges in order to maximize wood surface quality.
Context Improving surface roughness of wood in rip sawing by optimizing the sawtooth parameters is a significant topic of focus in the research of wood processing. However, existing research focuses mainly on the optimization of the sawtooth parameters of the major cutting edges without taking into ac- count the influences of length and angle of the side edges on surface roughness. Thus, adaptive parameters for the side edges should be proposed.
Aims This study analyzes how the different parameters of side edges influence surface roughness when circular saws are used, and aims to resolve disparities between high feed speeds and better surface roughness.
Methods In particular, this article presents the use of a sawtooth with a mic- zero- degree radial clearance angle. Northeast China ash (Fraxinus spp.) serves as the material for conducting this rip-sawing experiment. Nine types of sawtooth geometries at different feed speeds are used to study the influences of both the different radial clearance angles and the straight length of the zero- degree radial clearance angle on surface roughness (Ra).
Results Surface roughness increases with the increase in feed speed, and the smaller the radial clearance angle of the sawteeth, the smaller the surface roughness. When the sawteeth have a mic-zero-degree radial clearance angle, the sawing surface roughness is lower than that of the value of sawteeth with radial clearance angles, especially when the straight length of the zero- degree radial clearance increases from 0 to 0.5 mm, in which case the decrease is most obvious.
Conclusion Surface roughness depends, to a certain extent, on the depth of the saw notch. A small part of the side edge that forms the sawing surface participates in the actual cutting, and the length of this section is approximately equal to the feed per tooth. Sawteeth with mic-zero-degree radial clearance angles can improve the surface quality of sawing. Also, if the other cutting factors remain unchanged, surface roughness can be improved and friction can be reduced between the side edges and the wood by increasing the feed speed.

• 出版日期2017-6
• 单位中国林业科学研究院