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In this study, softwood cedar of Lebanon (Cedrus libani A.Rich.) and hardwood black poplar (Populus nigra L.), turned into cylinders by turning, were subjected to a surface densification process. Densification was carried out on the lathe using the spinning roller designed and manufactured for this purpose. Hardness, brightness and roughness (Rz) measurements were carried out on undensified and densified regions of the cylindrical solid wood materials. An increase in hardness and brightness and a decrease in roughness values occurred under all densification conditions. The highest surface hardness values occurred in cedar of Lebanon at 0.081 mm/rev feed, 200 rpm spindle speed, and 1 mm densification depth. On densified wood surfaces, as the feed from the densification parameters increases, the hardness decreases, and as the densification depth increases, the hardness increases-. The effect of surface densification parameters on the gloss and roughness results of the samples shows no linear effect in terms of experimental parameters. In both species, lower spring back was obtained at low depth of densification.

In this study, specimens from Scots pine (Pinus sylvestris L.), Anatolian chestnut (Castanea sativa Mill.) and Eastern beech (Fagus orientalis Lipsky) tree species, prepared according to ISO 3129, were conditioned according to TS ISO 13061-1. Cellulosic varnish, water-based varnish, and glass polish varnish were applied to their surfaces in accordance with ASTM-D 3023 principles. In the study, roughness (TS 2495 EN ISO 3274 and TS EN ISO 21920-3) and gloss (according to TS EN ISO 2813) values of the samples were calculated after hot and cold check test. Varnished test specimens prepared in 100 mm × 100 mm ×10 mm dimensions were first kept in drying oven at (50±5) °C for 1 hour, then were kept in conditioning room for 1 hour, and then at (-20±2) °C for 1 hour, according to ASTM D1211-97. These processes were accepted as one cycle, and tests were continued until 15 cycles. Afterward, glossiness was measured as perpendicular and parallel to fibers at 60º with a gloss measurement device, and surface roughness values of Ra and Rz were determined with a surface roughness measuring device. According to the results obtained, Scots pine (Pinus sylvestris L.), Eastern beech (Fagus Orientalis Lipsky), and Anatolian chestnut (Castanea sativa Mill.) varnish-coated wood material surfaces all showed a decrease in gloss values after hot-cold shock effect. While an increase occurred in Rz values of roughness for all wooden surfaces, Ra values roughness increased for Scots pine and chestnut and decreased for eastern beech. Gloss and roughness values of surface-treated wood materials against changing weather conditions can determine usefulness of the surface material used. The findings obtained in this study can be useful to manufacturers who use wooden products in the design of marine vehicles and those who export furniture to countries in different climatic conditions.

It is important to evaluate the effect of machining and wood machining properties on surface quality to determine and upgrade the data on wood machining properties and to defi ne convenient usage areas for some native wood species of Turkey. European black pine (Pinus nigra Arnold) and cedar of Lebanon (Cedrus libani A. Rich) are two softwood species and sessile oak (Quercus petraea Lieble) and black poplar (Populus nigra L.) are two hardwood species commonly used and grown in Turkey. These trees species were selected as experimental material for the study. Roughness measurements are significant in the determination of wood surface quality for use as a final product. This study evaluated roughness measurements after planing and sanding operations, and found that the highest value for average roughness (Ra) was observed as 6.780 μm. in sessile oak, followed by black poplar at 6.338 μm, cedar of Lebanon at 4.836 μm, and black pine at 4.740 μm. The average roughness values for wood in directions perpendicular to the grain and along the grain from highest to lowest were sessile oak, black poplar, black pine, and cedar of Lebanon.

The main objective of this study is to determine the effect of heat treatment on the machining properties of solid wood material and determine the optimum cutting parameters to obtain surfaces with minimum surface roughness. In line with this goal, Siberian pine (Pinus sibirica) wood species, widely used in the woodworking and furniture industry, was chosen as the experimental material. The heat-treated (at a temperature of 190 °C for 2 hours) and untreated samples were machined using two different cutters (carbide upcut milling cutter and carbide compression milling cutter) with 5 mm diameter at 1000, 1500 and 2000 mm/min feeds, 8000, 12000, 16000 rpm spindle speed, 50, 75 and 100 % stepover on the CNC machine. Surface roughness values (Ra and Rz) were measured to evaluate the obtained surfaces according to ISO 468 (2009), ISO 3274 (2005), and ISO 4287 (1997) using a contact profilometer. When the data was evaluated in general, the lowest roughness value for Ra occurred in upcut milling cutter, with 50% stepover, 12000 rpm, 1000 mm/min feed on untreated solid wood material. The highest roughness value for Ra occurred in a compression milling cutter, with 100 % stepover, 16000 rpm, 2000 mm/min feed on heat-treated solid wood material. It has been observed that the feed is the most critical parameter affecting the surface roughness.