Abstract
To clarify the effects of bed angle， seven categories of timber were finished with smoothing planes having sharpened blades bedded at bed angles of 31 to 44 degrees. The surface roughness of these specimens was measured with a surface roughness tester for comparison.
Except for lauan， which showed different characteristics， all other categories of timber had smaller values for the average maximum peak –to –valley height (Rmax) of the roughness smaller bed angles and larger blade tip angles. As for the relation ship between the maximum roughness (Rmax) and the bed angle， larger bed angles resulted in larger values of roughness and variance. When the bed angle becomes smaller， the variance again becomes larger. Thus， the smallest variance was measured when the tangent of the bed angle was 0.8.
