Different CNC machining condition of paulownia wood by CNC; Influence on the abbott roughness parameters

Abstract

The aim of this study was to investigate the factors affecting surface quality of paulowniawood during milling by advanced computer numerical control (CNC) machine. For this aimwood logs were provided and were converted to proper sizes (2.5 x 10 x 15 cm) and then airdried. The Variable of this study were spindle speed of machine (10000 and 18000 rpm),feeding rate (6 and 12 m/min), cutting depth (1and 5 mm), cutting method (down and upmilling)and cutting pattern (tangential and radial). Roughness of cut specimens edge wereevaluated by profilometer method according to ISO 13565 standard. For evaluation of surfacequality Abbott group parameters (Rpk, Rk, Rvk) were used. Degree of effective of theparameters was evaluated by fractional factorial design as completely random design atconfidence level of 95%. The result showed that spindle speed, cutting method and feed rate areinfluencing factors on surface quality of milled specimens and their effect was significant. Withincreasing spindle speed and decreasing feeding rate the roughness decreased and surfacequality improved. In up-milling cutting method, degree of roughness was higher andconsequently surface quality was inferior. It is to be noted that cutting method in comparison toother factors had the high influence on surface quality. The rest variable did now haveindependent influence on surface quality at 95% Confidence level.

Keywords

• Milling
• Cutting speed
• Feeding rate
• Profilometery
• Surface roughness