In this study, surface roughness and burr were investigated in drilling of pure and carbon black reinforced high-density polyethylene at three cutting speeds and feeds with three drill point angles. The measurement results of surface roughness of drilled holes were evaluated by Taguchi and analysis of variance statistical methods to specify the optimal drilling parameters and the effects of selected drilling parameters. According to the results, lower surface roughness and fewer burrs were obtained in drilling at high cutting speed and low feed with drill tools having small point angle and it was specified that the carbon black reinforcement reduced the surface roughness. Additionally, the optimal drilling parameters were determined as drill point angle of 80°, feed of 0.1 mm/rev and cutting speed of 120 m/min and the most effective parameter was found as drill point angle and the least effective parameter was found as feed.
