EFFECT OF ROTATIONAL SPEED AND WOOD SPECIES ON ROUGHNESS OF MACHINED SURFACE.

In this study, the surface roughness values of planed beech-wood (Fagus L.), thermally modified beech-wood, oak-wood (Quercus L.) and fir-wood (Abies alba Mill.) specimens were examined. The specimens were machined by planing in radial directions with two knives at 12 m/min feed speed. The cutting depth of planing was constant (1,0 mm) and knife rake angle was 15o. The machining experiments were carried out using a single cutter-block of a Weinig Powermat 500 with rotational speed of 5000 and 8000 (RPM) and the cutter-block diameter of 125 mm. Surface roughness was measured at the radial face of each sample according to DIN 4768 (1990). Comparison between the results of surface roughness of sample groups planed with different rotational speed showed significant difference. Better results of the machining performance have been obtained with the decreasing rotation speed for the softwood and with the increasing speed of rotation for hardwood. [ABSTRACT FROM AUTHOR]