Comparative Surface Quality of Maple (Acer pseudoplatanus) Cut through by CNC Routing and by CO2 Laser at Different Angles as Related to the Wood Grain

Abstract

The evaluation of surface quality is an important criterion to understand the effect of the cutting angle in relation to the grain and of the processing tool on wood. This paper examines, in a comparison, the surface quality of maple cut through by CNC and CO2 laser, for different angles with regard to the wood grain: 0°, 15°, 30°, 45°, 60°, 75°, and 90° and at different feed speeds of the CNC router: 2; 2.5; 3; 3.5 and 4 m/min. The direction of processing as related to the grain was a more significant factor in comparison with the feed speed when CNC was used, with best options for 0°, 90° and 75° and worst for 15°, where fuzzy grain was predominant, followed in order by 30°, 45°, and 60°, where pull-out material prevailed. The laser smoothed the core roughness, Rk, with no significant differences as related to the wood grain direction and enhanced an anatomical waviness earlywood-latewood, with the earlywood processed deeper. As the cutting advanced from along to across the grain, the laser uncovered more wood anatomical details and with less destruction. No significant differences in Rk between CNC cutting and laser processing were found for angles: 0°, 60°, and 75°, but surfaces processed at 15°, 30°, and 45° were significantly rougher in the case of CNC cutting. Comparative FTIR investigation of surfaces cut by laser and CNC (at 0° and 90°) clearly revealed temperature-induced chemical changes, such as hemicelluloses degradation, possibly demethylation and advanced condensation in the structure of lignin, in the case of laser processing.

The Effect of CO2 Laser Engraving on the Surface Structure and Properties of Spruce Wood

“…The results confirm that the wood surface engraving with a CO 2 laser resulted in significant increases in roughness parameter values, which is in accordance with other research [8,12,14,15,19]. A more significant roughness increase was obtained by increasing n than by increasing the P e (Figure 6).…”

“…The roughness is mainly attributable to non-uniform wood mass degradation within an annual ring due to differences in density between early wood and late wood [8]. The roughness is notably affected by the fibre angle under which the wood surface is treated [15]. The published results confirm that, via appropriate adjustment of the CO 2 laser engraving parameters, targeted changes in the wood surface morphology can be ensured [8,13,14].…”

“…The changes in the colour coordinate values, L*, a* and b*, are relatively easy to measure and, as such, they can serve as indicators of significant chemical changesand changes in other wood properties-resulting from a specific surface treatment (IR radiation, UV radiation, thermal modification and similar) [29]. This is the main reason for the interest in this issue today [6,8,13,15,25,26,[30][31][32][33].…”

Degradation of Stains from Metal Surfaces Using a DBD Plasma Microreactor

“…To date, they have been extensively used in numerous fields, such as construction, electronics, automobiles, electronics, and aerospace, etc. Surface quality is an important criterion to evaluate the overall performance and functionality of metals as it is closely related to their key properties like mechanical strength, wear resistance, hardness, corrosion protection, and biocompatibility [ 1 ]. However, the surface contamination of metals is inevitable during practical applications, which may seriously affect their mechanical properties and functionality [ 2 ].…”

Evaluation of the Surface Irregularities of the Cross-Section of the Wood after CO2 Laser Cutting

“…However, in the case of a cross-section, it becomes insufficient, since through the most used filter value λc = 2.5 mm, there is a significant attenuation of the amplitude for a wavelength of irregularities greater than 2.5 mm. However, if the height irregularities between the less dense earlywood and the more dense latewood after machining are defined as anatomical waviness [29], it is necessary to deal with the irregularities with a wavelength higher than 2.5 mm. The most common width of annual rings, within which the difference in earlywood and latewood will show, is in our climate zone in the range of 2-5 mm.…”