Examples of angles

Example : appropriate angles to cut resinous wood on a D.160 machine

∝ = 35° + β(43°) + ℘(12°) = 90°

① The tooth shape should facilitate the removal of chips. It is therefore important for the tooth gullet to be well curved.

② The chip width should be between 0.5mm and 1.5mm. A too small chip reduces the cutting life of the blade. A too big chip rips the wood too harshly.

Thickness is determined by the following ratio :


Thickness in mm =  feeding speed in m/min x pitch in mm
          60 x cutting speed in m/s


N.B. : Cutting speed (S) is the linear speed of the blade expressed in meter per second.


S =  π x diametre of wheels (in m) x N (number of wheel rounds per minute)
                                                            60



N =  of the engine in rounds per minute x diametre of engine wheel
                                        Diameter of the wheel


Example :

D.140 machine :

  • Engine speed : 1450 rounds/min
  • Engine wheel : 220mm
  • Machine wheel : 650

N =  1450 x 220
      650
 = 490 Rd/min V =  3.14 x 1.40 x 490
             60
 = 35.9 m/s