JOURNAL OF OIL PALM RESEARCH (SPECIAL ISSUE - APRIL 2006) 114 Journal of Oil Palm Research (Special Issue - April 2006), p. 114-121 AN INVESTIGATION ON THE MECHANICAL PROPERTIES OF TRUNKS OF PALM OIL TREES FOR THE FURNITURE INDUSTRY THANATE RATANAWILAI*; TANONG CHUMTHONG* and SITTIPON KIRDKONG* Keywords: palm oil wood, rubberwood, teak, mechanical property, furniture. Date received: 18 November 2005; Sent for revision: 26 December 2005; Received in final form: 17 January 2006; Accepted: 13 February 2006. ABSTRACT High quality wood furniture requires several factors, such as properties of woods, product design, production process and control, which must be considered. Mechanical properties are considered to be some of the most important factors at the stages of product design and material selection. A comparison of mechanical properties between palm oil wood, rubberwood and teak, which are widely used in the furniture industry, is the objective of this study. The base, middle and top samples were cut from palm oil trunks and seven parameters were measured using standard methods and procedures. They included specific gravity, moisture content, bending stress, tensile stress perpendicular-to-grain, hardness, compressive stress parallel-to-grain, and impact stress. The overall results showed that the mechanical properties of palm oil trunk were approximately two times lower than those of teak and rubberwood. Different portions of the palm oil trunk also gave different mechanical properties. It was found that the base of the palm oil trunk gave the lowest modulus of elasticity than the top portion but provided higher hardness than the others. Hence, this study provides essential information on the suitability of palm oil wood for applications in the furniture industry. * Department of Industrial Engineering, Faculty of Engineering, Prince of Songkhla University, Hatyai, 90112, Songkhla, Thailand. E-mail: thanate.r@psu.ac.th INTRODUCTION Over the years, wood has been utilized for homes and other structures, such as furniture and tools, because of its unique characteristics. Wood furniture is one of the most popular products among a variety of wood utilizations. At the present time, the growing social demands for wood furniture have led to a continuous effort in finding alternative wood resources for the furniture industry. Teak used to be the most popular wood for furniture manufacturing; however, the price of teak has increased rapidly as teak, itself, is considered to be a hard-to-find wood. Rubberwood has become another source of raw material for the furniture industry and has been widely used. Rubber plantations can be found everywhere in the region of southern Thailand and Malaysia. At the same time, palm oil plantation is rapidly growing in both of the mentioned regions and is tending to replace the rubber plantations in many areas. Palm oil tree has proven itself to be an important economic resource in the tropical areas of Southeast Asia, especially in the southern part of Thailand and Malaysia. A wide array of products has been developed from various portions of the palm oil tree. For instance, fibres from fronds of palm oil tree have been used to make particleboards (Lamsuk, 2003); nonetheless, palm oil trunk has not yet been used effectively. In order to fully utilize the woods, understanding their physical and mechanical properties is vital. All wood is basically composed of cellulose, lignin, hemicelluloses and minor amounts of extraneous materials (5% to 10%) that are contained in a cellular structure (Forest Product Laboratory, 1999). A unique characteristic of wood is depended upon the variations in the characteristics and amount of these components, as well as differences in its cellular structure. Therefore, to use wood to its best advantages and most effectively in furniture industry, physical and mechanical properties of