Abstract
One point of japanese carpenter concern on his task was to produce the best surface smoothness of wood in planing, so in traditional wood building only planing surface was used for the structure member and interior fittings without polishing or painting.
The purpose of this study was to provide the information on surfacing of wood with finishing plane. Test specimen， sap wood of japanese cryptomeria (sugi)， was planed by 8 planes and was measured surface roughness on the part of spring wood by means of knife edge sensor.
Test result may be summarized as follows:
1. Measured roughness (Rmax : maximum roughness defined by DIN) expressed the wood surface condition comparing with surface photograph and eye observation.
2. Minute wooly grain roughness observed naked eye was approximately Rmax>9μm.
3. It was considered that cutting angle affected the surface roughness and showed most few roughness in cutting angle 39°.
4. It was difficult to find a certain relation between roughness of blade edge (Rmax ＝4～10μm) and wood surface roughness.
5. In successive cutting test， accumulate length of 15M wood planing did not change the average roughness of wood surface in blades finely sharpened. But accumulate length of 30M wood planing showed the surface roughness increase in some blades.
