| Summary: | The saw milling process is considered as an important phase of the industrialization of oaks and of the quality of the sawn lumber. The quality control of the sawing process is analyzed, as well as the traditional sawing pattern with the quarter sawing (flat grain vs vertical grain) and their effect on the lumber yield (lumber recovery factor), on the processing time and on the proportion of width dimensions of lumber. Logs of Quercus laurina, Q. candicans y Q. acutifolia were processed in a 8-in wide band sawmill, with traditional saw machinery for pine, The sawing variation (St) was of 3,93 mm, which is considered high showing the low quality of the sawing system, the obtained mean was 25,36 mm and the optimum sawing dimension was of 28,71 mm. The difference means that a large percentage of boards (80 %) was not able to be graded in the thickness category of ¾ inches. The lumber recovery factor of the traditional system was 55,83 % and in the quarter sawn was 52,31 %. The sawing time to process 1 000 board feet in the traditional system was 73 minutes being of 103 minutes in the radial system, which represented 41 % of the traditional system. With the quarter sawn system, a large proportion (77 %) of narrow boards (4-in and 6-in) and small percentage (23 %) of wider than 8-in boards were generated. With the traditional sawing system, the proportions were significatively reversed, for 8-in or wider an 88 % was achieved.
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