In this second report, the polyethylene glycol (PEG) trea tment which reduced friction between wood and steel in previous report was adopted as an application to wood machining and the machinability in cutting or sanding PEG treated wood was examined. The main resu1ts obtained are as fol1ows. (1) A1though the bending strength 0 f most PEG trea ted wood is reduced as compared with untreated wood, that of wood treated with PEG of higher molecular weight such as PEG 4000 increases. (2) The horizontal and vertical cutting resistances in cutting parallel to the grain are considerably reduced by PEG treatment. In this case, although the rate of reduction in cutting resistances becomes larger at the higher retention of PEG, it is independent of molecular weight of PEG. (3) The PEG treatment furthermore leads to an increase in radius of chip curvature and a decrease in roughness of cutting surface. (4) It is conjectured that the above reduction in cutting resistances is principally due to the decrease in strength in the case of wood treated with PEG of lower molecular weight and due to the decrease in coefficient of friction in the case of higher molecular weight. (5) The cutting resistance in cross sectional cutting is also reduced by PEG treatment and the cutting surface is improved. (6) In sanding, although PEG treatment reduces sanding resistance and improves sanding surface, it lessens the rate of stock removal.
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