With the servo-upgrade of the cnc-mill complete we are now beginning to run the kind of jobs that weren't previously possible. Stepper motors simply don't give the kind of 3D contouring capability and reliability for running 3-4 hour finish jobs like these. The finmould is finished with a 6 mm ball-nose cutter.
Jari made these moulds in steel, but it's possible to cut them in aluminium too. The fin mould here has a NACA 0010 section and the rudder has a thicker NACA 0015 section. With the precision that cnc-cutting provides we hope that the fin can come out of the mould quite complete and fit a cnc-cut finbox/bulb without much manual fitting.
We can produce fin, rudder, and bulb moulds in steel or aluminium on a small scale. Get in touch by email or by commenting below if you are an interested IOM-builder.