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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.

In this study, the effect of machining parameters on the surface quality of the machining of different surfaces of the Oriental beech (Fagus orientalis Lipsky) tree species used in the woodworking and furniture industry was investigated and it was aimed to determine the optimum machining parameters. The experiments were carried out at two different dept of cut (depth of cut 3.33 mm or 2.5 mm per machining, total 10 mm dept of cut) by using two different 8 mm diameter cutters at 8000, 12000 and 16000 rpm at feed rates of 1000, 1500 and 2000 mm/min. Surface roughness measurements were made according to ISO 4287 by using a test device with the stylus method on the surfaces obtained in different sections. Ra and Rz roughness measurements were performed on the surfaces obtained as a result of machining. It has been observed that the machining parameters have an effect in different rates on the surface roughness and the results are evaluated by comparing with the literature. The lowest average roughness (Ra=5,18 µm) value was obtained in 3-layer processing, 1000 mm/min feed rate at 16000 rpm, cutter type 2 for measurements perpendicular to the fibers on floor surfaces. The lowest values (Ra=2,84 µm) on the side surfaces were obtained as 4-layer machining, 1000 mm/min feed rate at 16000 rpm, cutter type 1 for measurements perpendicular to the fibers.

Mobilya tasarımı, mimari tasarım ve endüstrinin birçok dallarındaki tasarımlara benzerdir. Bu dallarda kullanılan tasarım yöntemleri mobilya tasarlamada da kullanılabilmektedir. Tasarım sürecinde elde edilecek sonuçların çeşitliliği tasarımcıya bağlıdır. Temel tasarım elemanlarının etkin bir biçimde kullanılması tasarım süreci açısından vazgeçilmez bir gerekliliktir. Bu nedenle ürün tasarımcıları tasarım süreçlerine yenilik getirerek; tek başına düzensiz görünen parçaları, tasarım elemanlarını oluşturan nokta, çizgi, yön ve doğrultu, yüzey, alan, orantı, ölçü ve boyut, biçim ve form, renk, doku’dan faydalanarak sonuçlandırmaktadırlar. Tasarım elemanlarının etkin kullanımı ve insan psikolojisi üzerindeki etkisinin bilinmesi tasarlanan mobilyanın istenen tasarım hedefine ulaşmasını sağlayacaktır. Çalışmada tasarım elemanları hakkında öz bilgiler verildikten sonra, insan psikolojisi üzerindeki etkisi açıklanmıştır. Mobilya tasarımı yapan kişi ve kurumlar insan psikolojisinin önemli olduğu, ürünü beğenme ve satın alma arzusunun oluşturulmasının gerektiği ticari bakış açısıyla bu faktörleri optimum kullanabileceklerdir. Özellikle ortak kullanım alanlarında (okul, hastahane, otel, konferans salonu, lobi vb.) bu faktörleri göz önüne alarak tasarımların gerçekleştirildiği mobilyalar kullanıldığında istenilen psikolojik etki (huzur, hareket, güven vb) oluşturulabilecektir. Sonuç olarak her tasarım parametresinin uygun bir şekilde ve bilinçli olarak kullanımı ile tasarlanan ürünün kullanıcılar üzerinde etkisi istenilen şekilde olabilecektir.

In this study, the effects of distances between the fastener types and edges of member were investigated on bending moment of L-type disassembled furniture corner joints. For this purpose, Clamex P14 and Tenso P14 fasteners obtained from Lamello company and melamine-coated medium density fiberboard (MDF-lam) material was used for test specimens. The distances between fasteners and edges of member were determined as 3, 4 and 5 times the materials thickness (54, 72 and 90 mm). Diagonal compression test was applied to 60 specimens under loads as specified in according to (ASTM D 1037- 06a, 2006) standard in the universal test equipment. According to the results of the experiment, the highest bending moment value was obtained on the distance between the clamex P14 fastener and the edges of member was 90 mm in the test samples, while the lowest bending moment value was obtained on the distance between part edges was 54 mm with the Tenso P14 fastener in the test samples. Diagonal compression test was applied to 60 specimens under static load as specified in ASTM-D 1037 standard in the universal test equipment

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.

The main objective of this study is to determine optimum cutting parameters in order to specify the effect of densification by compressing on the processing properties of solid wood material and to achieve the best surface quality in materials densified at different rates. In line with this goal, the widely grown and low-density black poplar (Populus nigra) tree species were selected as the experimental material. Samples, which were compressed and densified by Thermo-Mechanical method at 0 %, 20 % and 40 % ratios, were processed at 1000 mm/min, 1500 mm/min and 2000 mm/min feed speeds and in 12000 rpm, 15000 rpm, 18000 rpm rotation speed on a computer numerical control machine by using two different cutters. Surface roughness values (Ra and Rz) were measured in order to evaluate surfaces obtained. Smoother surfaces were obtained in computer numerical control machining of densified samples. The lowest surface roughness values occurred in 40 % densified samples, which were the densest. The lowest surface roughness was obtained when 40 % densified samples were processed with cutter no.1, at 1000 mm/min feed speed and at 18000 rpm.

The purpose of the study is to obtain optimum processing conditions by investigating the effect of machining parameters of bamboo (Bambusa) material on surface quality. Evaluation was performed for four machining parameters (cutters type, spindle speed, feed rate and depth of cut) and their effects on surface roughness. According to obtained data, roughness values increased with increasing machining depth. Increase in roughness values between 8000 rpm and 10000 rpm, decrease in roughness values between 10000 rpm and 14000 rpm, and increase in roughness values between 14000 rpm and 16000 rpm was observed. Roughness value increased with increasing cutter feed speed. Roughness value decreased by increasing number of blades in cutter in cutter type. The lowest roughness value was obtained at a machining depth of 2 mm at a spindle speed of 14000 rpm, a feed rate of 1000 mm/min and a cutter type 3 (four flute spiral end mill).

In this paper, the optimization of computer numerical control (CNC) machining parameters were conducted using the Taguchi design method on the surface quality of massive wooden edge glued panels (EGP) made of European larch (Larix decidua Mill). Three machining parameters and their effects on surface roughness were evaluated. These parameters included tool clearance strategy, spindle speed, and feed rate. An analysis of variance (ANOVA) was performed to identify the significant factors affecting the surface roughness (Ra and Rz). Optimum machining parameter combinations were acquired by conducting an analysis of the signal-to-noise (S/N) ratio. Optimal cutting performance for the Ra and Rz was obtained for the cutter at a tool clearance strategy of an offset 16000 rpm spindle speed and 1000 mm/min feed rate. The surface roughness, both the Ra and Rz, increased with increasing feed rate. Optimal cutting performance for Ra and Rz was obtained for a tool clearance strategy of an offset 16000 rpm spindle speed, and 1000 mm/min feed rate cutting settings. Based on the confirmation tests, Ra decreased 2.2 times and Rz 1.8 times compared to the starting cutting parameters.

An artificial neural network (ANN) approach was employed for the prediction and control of surface roughness (Ra and Rz) in a computer numerical control (CNC) machine. Experiments were performed on a CNC machine to obtain data used for the training and testing of an ANN. Experimental studies were conducted, and a model based on the experimental results was set up. Five machining parameters (cutter type, tool clearance strategy, spindle speed, feed rate, and depth of cut) were used. One hidden layer was used for all models, while there were five neurons in the hidden layer of the Ra and Rz models. The RMSE values were calculated as 1.05 and 3.70. The mean absolute percentage error (MAPE) values were calculated as 20.18 and 15.14, which can be considered as a good prediction. The results of the ANN approach were compared with the measured values. It was shown that the ANN prediction model obtained is a useful and effective tool for modeling the Ra and Rz of wood. The results of the present research can be applied in the wood machining industry to reduce energy, time, and cost.

Heat treatment changes some physical, mechanical, and chemical properties of wood. Inorganic borates have been used as wood preservatives for many years. The aim of this study was to investigate the effects of impregnation chemicals on some mechanical properties (bending strength (MOR), modulus of elasticity (MOE), tensile strength parallel to the grain (TS), compression strength parallel to the grain (CS), and shear strength parallel to the grain (SS)) of heat-treated oak (Quercus petraea Liebl.). For this purpose, the oak wood specimens were impregnated with 5% aqueous solution of boric acid (BA) and borax (BX). Then specimens were heat-treated at 160, 190, and 220 °C for 2 and 4 h. According to the results of the study, borax retention value was higher than boric acid. The bending strength, modulus of elasticity in bending, tensile strength parallel to the grain, and shear strength parallel to the grain decreased due to heat treatment. The highest mechanical strength losses were determined in samples heat treated at 220 °C for 4 h. Generally the mechanical strength losses of samples impregnated with borax were lower than non-impregnated controls and specimens impregnated with boric acid.