Would a billet aluminium blades and boards work?
Would they be stronger?
Would they be lighter?
I'm gonna go out on a limb and say they'd be definitely cheaper. Once you've got the file, load up a blank in a 4 axis cnc mill and basically walk away. Plus polished boards would be frickin' cool. Or even anodized. Might want to make the top removable, a bent board could be trouble if you couldn't pull it out the top......
There are many alloys available, some are very strong, some not some have excellent corrosion behaviour, some not, and so on. But fact is that the right alloy is resistent to salt water and strong (as proven by thounds of masts). It has similar strength to hand layed up glasfibre, but less than carbon. Best production process would be extruding (if you can live with a straight board), not machining. Topcats use extrude alu rudders since ever. They have decent quality and are unkaputtbar (undestructable). At all the whole rudder system is a nice one on the Topcats.
Not cheaper than some glass boards though.
http://www.topcat.de/shop/index_e.htm . The rest of the boat is fairly outdated...
Alu rudders wouldn't be particular heavy, about the same or a bit more than glass fibre boards of the same strength and size and maintenance free by the way.
Cheers,
Klaus
