Optimization of the Sanding Process-The Case of Rubberwood

摘要

Rubberwood (Hevea brasiliensis) is one of the most important raw materials in the furniture manufacturing sector in the South East Asian region. Despite its wide use, the material has inherent machining problems, which affects the final quality of furniture produced. The prevalence of tension wood in the material leads to high incidence of fuzzy grain and tear out after machining processes, and these machining defects must be rectified through the subsequent sanding process, to produce smooth, defect-free surface. However,the sanding process is often economically costly and there is a need within the industry to develop industrial guideline to optimize the process. Therefore, a series of experiments were carried out to optimize the Rubberwood sanding process, using a two-head SANDING MASTER wide-belt sander, using aluminum oxide abrasive belt of the grit sizes 150 -180. The used Rubberwood machined planks had different number of cutting marks per inch (18, 20, 22, 24, 26) to reflect industrial practice. It was found that the sanding process of Rubberwood was optimized when machined planks with more than 24 cuts per inch, under the 150-180 sanding grit configurations, were used. The experimental machined planks with lesser cutter marks required two or more passes,to achieve the desired level of surface smoothness. Surface roughness measurements made using a contact-stylus profilometer also indicated that the final surface roughness was optimized when machined planks with more than 24 cuts per inch were used. This study provides evidence to suggest that optimizing the sanding process of Rubberwood will require the use of machined planks with more than 24 cuts per inch, using the sanding grit sequence of 150-180.