Effects of helix angle and feed per knife on cutting forces, noise, and power consumption produced during helical planing of sugar maple wood

A conventional straight knife cutterhead and three helical knife cutterheads were tested for planing sugar maple wood (Acer saccharum Marsh.). Effects of helix angle and feed per knife (FK) on maximum cutting forces, sound level, and power consumption were evaluated. A 3-axis dynamometer, an array microphone, and a watt transducer were used to simultaneously record the forces, sound level, and power consumption during machining, respectively. Parallel (F P ), positive and negative normal (F NP and F NN ), lateral (F L ), resultant (F R ) forces, and sound level increased as FK increased. Helical tools produced lower F P , F NP , F NN, and F R . Parallel forces tended to decrease as helical angle increased. Differences among helical tools were not significant for normal forces. Helical tools produced higher F L at medium (2.9 mm) and high (4.7 mm) feeds per knife. F R decreased as helix angle increased. The impacts of these cutting forces on the appearance of surface defects and ways to reduce them were discussed. Helical cutterheads considerably generated lower sound pressure level, with a maximum difference of up to 8 dB(A). At low FK (1.3 mm), helical tools required slightly lower cutting power.