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Volumes of timber logs (dead trees) in the Volta Lake in Ghana, that had become a dead trap for water transportation, were being extracted for utilization to increase the timber resource base. Unfortunately, their properties were not known for efficient promotion and utilization. The influence and relative significance of machine surface planing and sanding parameters in the production of good quality timber surface finish on four underwater timber species from the Volta Lake were investigated. The preparation of test specimens, testing, evaluation and grading of the tests specimens were conducted according to ASTM-D 143, 1666-87 and DIN 4768. A cutting depth of 2 mm was made constant. Wood specimens were planed and sanded at 12% moisture content and the surface qualities obtained were visually graded. Surface quality performance increased with decreasing rake angle and feed speed. Low rake angle of 15° with 6 m/min and 9 m/min feed speeds resulted in a high planing quality. The degree of magnitude of the chipped/torn grain defects decreased with decreasing rake angle and feed speed. Grit sizes of sand paper had significant effect on the surface quality of the four species. The chipped/torn grain defects observed were eliminated from all the wood species with grit size 40. High surface sanding quality was registered for all the species with grit 150.

Poor machining of wood generates more residues which leads to low recovery in wood processing. Therefore, the availability of appropriate wood machining techniques would promote efficient utilization of logs. This study looked at the shaping and sanding properties of Gmelina arborea - a lesser-known species in Ghana - in order to promote its efficient utilization. Six trees from plantations at the Wet Evergreen and Dry Semi-Deciduous Forest Zones were extracted and processed into lumber using LT 15 horizontal wood-mizer. The average moisture content of samples just before the test was 14.57%. Specimens were prepared in accordance with ASTM D 143-83 and ASTM D 1666-87 (2004) for the sanding and shaping tests. The effects of tree location, grit size and spindle speed on sanding and shaping properties of Gmelina arborea wood were assessed using the visual approach. For the sanding test, grit size P80 was the best sandpaper to remove chipped and torn grain defects from the surfaces of Gmelina arborea lumber after planing. Spindle speed 10,000 rpm gave the best shaping output so it was recommended for shaping Gmelina arborea timber grown in Ghana. For the shaping operation, wood samples obtained from the Dry Semi-Deciduous Forest Zone had better surface quality than those obtained from the Wet Evergreen Forest Zone. A similar trend was obtained for the sanding test. The most common defects observed during grading of the shaped specimens were raised, chipped and fuzzy grains and those observed for the sanded specimen were fuzzy and scratchy defects. At 5% level of significance, tree location and spindle speed had significant effect on the surface quality of the shaped specimen.

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The uses of wood and wood-based materials in everyday life ranging from domestic to industrial purposes have called for renewed updating of the information and knowledge on various thermal properties of the materials at various stages and classifications. This paper investigates the thermal properties (specific heat capacity and thermal conductivity) of some selected tropical hard wood species using the method of mixtures and the Lee's Disk method respectively. The results show that the thermal conductivity of the selected wood species fall within the general range of 0.1-0.8 W/mK for tropical wood materials, with Celtis mildraedii having the least thermal conductivity of 0.08W/mk and Strombosia glaucescens the highest value of 0.392 W/mK. The specific heat capacity was highest for Holorrhena floribunda (1.97 J/g.K) and the lowest for Pterygota macrocarpa (1.01 J/g.K). These results can be used for testing the validity and efficiency of hard woods used for domestic and industrial applications.