The angles
The choice of angles is very important because it determines :
- The penetration power of the blade into the wood
- The rigidity of the tooth
- The cutting strength
Given that the sum of the 3 angles equals 90°, each angle determines the other.
a) Rake angle Â
It should be as wide as possible in order to easily cut the wood fibres. It varies between 25° (hard wood) and 35° (soft wood).
NB : The hook angle depends on the tool support and the type of wood to be cut (see table below).
b) Nose angle β
It ensures the rigidity of the tooth and varies between 40° and 55°.
c) Clearance angle D
It varies between 8° and 12°