Fig. 2
From: Wood machining with a focus on French research in the last 50 years
Cutting geometry and forces. α is the rake angle, ϕ is the angle between shearing plane and cutting direction, β is the friction angle between tool and material, θ is the wedge angle of the tool, ζ is the clearance angle, h is the chip thickness, t is the cutting depth of cut, FC is the cutting force parallel to cutting direction, FT is the thrust force orthogonal to cutting direction, FA is the rake force exerted by rake face on chip, FD is the clearance force exerted by clearance face on material