Analysis of theoretical machined surface roughness profile after sawing solid oak wood (Quercus robur L.) along the grain with a circular saw

Abstract

ABSTRACT The article presents an analysis of the influence of simulated circular saw teeth marks profile in relation to the anatomical roughness of solid oak wood (Quercus robur L.) on machining roughness after sawing along the grain with a circular saw in order to better understand this relationship and to improve the knowledge how this two factors can be separated for further analysis in real-world sawing and to try to quantify the minimum theoretical tooth mark height that could be distinguished from anatomical roughness of wood. The signal-to-noise ratio (SNR) of simulated circular saw teeth mark signal in relation to measured anatomical roughness signal of solid oak wood was used to determine the level at which saw teeth marks could have a meaningful impact on machined surface roughness. From the analysis it can be concluded that SNR values even as low as −13 dB can have enough information to be used for frequency analysis and filtering out of tooth marks signal. Averaging and longer sampling lengths provide much better SNR values and provide the frequency spectrum of the structural roughness signal of solid oak wood with the highest amplitude of less than 0.5 μm. If more favorable SNR values are to be obtained, sampling lengths should be much longer than what is standardly used and recommended in ISO 3274: 1996 (in this research cumulative sampling length of 600 mm was used).