Study on the in-process measurements of the surface roughness of Douglas fir green veneers with the use of laser profilometer

Abstract

The presented research concerns the use of a laser profilometer to measure the surface roughness of green Douglas fir heartwood veneers during the peeling process. It investigates the effect of various process parameters on the surface quality. Three experiments were carried out with a single variable factor for each experiment: log centration, soaking temperature and cutting speed. Moreover, the origin of the surface roughness of Douglas fir green veneers was investigated. The study shows that laser profilometer seems to be a useful equipment in online measurement of surface roughness of green veneers. Based on the experiment results it was stated that surface roughness of Douglas fir veneers is characterized by large differentiation depending on the location on the veneer. The performed analysis shows that the surface roughness of Douglas fir green veneer could be improved when using relatively high cutting speed, not too high steaming temperature and logs with a centered core. The presented study shows that the laser profilometer can be effectively applied to the measurement and evaluation of green veneers during the peeling process and that there is still an area to develop this methodology.

Toward the modelling of laminated veneer lumber stiffness and the influence of the number of plies

“…15) (Viguier et al 2018;Duriot 2021). The dispersions observed on the longitudinal Young's modulus of the [0°]1 specimens are thus mainly explained by the variability of the specimen density, the rest of the variation can be explained by the nature of the wood: wood veneer can be composed of earlywood (wood formed at the beginning of the growing season) and latewood (wood formed later in the season) (Stefanowski et al 2020); the variability of the out-of-plane angle of the fibre; the variability of the local density of the veneers or the presence of lathe checks.…”

New Perspectives for LVL Manufacturing from Wood of Heterogeneous Quality—Part. 1: Veneer Mechanical Grading Based on Online Local Wood Fiber Orientation Measurement

“…All logs were preliminarily soaked in water at 50 • C before peeling during a minimum of 36 h, intending to ease the rotary peeling by increasing the material deformability [16]. The linear cutting speed was automatically controlled by the machine at 1.5 m•s −1 [17]. The rotary peeling operation was carried out without the use of a pressure bar since the lathe was not equipped with a roller pressure bar.…”

Effect of chip thickness, wood cross-sections, and cutting speed on surface roughness and cutting power during up-milling of beech wood

“…Surface quality is a complex problem, dependent on many factors, including the heterogeneous wood structure and machining conditions (Malkoçoğlu 2007). Tests have been conducted on surface roughness of wood and wood-based materials, considering the effects of various factors such as cutting force (Aguilera and Martin 2001;Wang et al 2015), thermal wood modification (Budakçı et al 2013;Kvietková et al 2015;Pinkowski et al 2016), type of material (Davim et al 2009;Candan et al 2012;Bekhta et al 2014;Guo et al 2015;Stefanowski et al 2020), machining parameters (Kilic et al 2006;Malkoçoğlu 2007;Barcík et al 2009;Pinkowski et al 2018), tool wear (Gilewicz et al 2010;Aguilera et al 2016), species-specific characteristics (Thoma et al 2015), analysis of acoustic signals (Aguilera and Barros 2012), among others.…”