Study of Complex Helical Drill with a “S” Type Chisel Edge Tip Orient to Carbon Fiber Reinforced Plastics

Figure 9

The photos of holes drilled by each drill. (a) ψ = 50°. (b) ψ = 60°. (c) ψ = 70°. (d) ψ = 80°.

(a)

(b)

(c)

(d)