Machining with a computerized
numerical cutter (CNC) is the most accurate form of fin shaping
besides pre-preg high-compression moulding. CNC G10 is the
preferred manufacturing method for smaller fins as the strength
and toughness of G10 provides significant advantages. Because
no moulds are needed, each size can have individual outlines,
allowing for greater freedom in designing a finís plan shape.
This is a key criteria for fins with a high degree of curvature
along the leading and trailing edges: wave fins, freestyle
fins and cross over fins.
Compared to polyester, G10 is a far superior material with
greater strength and toughness. A G10 fin also provides a
quicker flex response and allows the designer to use thinner
sections for the same desired flex. The result is a faster
fin with more responsiveness.
Drake CNC cutters include a Vertical Machine Center Takano
VMC-1000 with an automated tool changer, a repeatability of
0.005mm and a resolution of 0.001mm, and a Mitsubishi Meldas
540 with 3 axis interpolation that cuts 3 axis simultaneously
at a feed rate of 5000m/min to 10000m/min.