MACHINING OF FOUR TIMBER OAK SPECIES FROM SIERRA DE JUAREZ, OAXACA

Abstract

Machining characteristics in the planing, boring, shaping, turning and sanding operations were assessed in four oak species, Quercus crassifolia, Q. laurina, Q. rugosa and Q. scitophylla. Tests were made according to the ASTM-D 1666-87standard. Best results of planing were obtained by combining all cutting angles tested with 7.5 m min-1 of feed speed, which means that the cutting angle had no marked influence on planing quality, and that the number of knife marks per inch (which is determined by the feed rate) was the factor that defined the quality that was obtained. The defect that occurred more frequently in this test was chipped grain, but in a superficial way. In boring, shaping, turning and sanding operations of the four species that were studied showed excellent machining characteristics. In boring and sanding the most frequent defect was “fuzzy” grain, which did not influence the final classification as it appeared in a superficial way, due, mainly, to the uniform size of the pores and the straight thread of wood, which counteract the characteristic coarse texture character of the taxa. For their excellent performance in regard to machines and tools, the wood of the four species is suitable to be used in the fabrication of finished products with a higher added value such as frames, wainscot, parquet flooring and furniture.