New High Aspect Ratio F-32 Rudder
A special high performance all carbon fiber rudder blade and case has been under development over the past year for the F-32 by Farrier Marine, and this is now nearing completion.
This premium all composite rudder system uses a new high aspect foil section that is much more resistant to ventilation, coupled with a quicker helm response. It can also be used on the F-9, F-31, F-33, and even as a maxi super rudder for the F-28. Blade Dimensions are 1770 high with a 316 chord.
Both case and blade are all carbon fiber, using an epoxy-vinylester infusion resin system, and this will be the most advanced F-boat rudder system on the market, with an all composite (carbon fiber) fully adjustable case. There are no metal parts, other than a few high tensile aluminum or stainless fasteners, and the actual pivot pin, while pivot bushings are custom machined from a special high performance plastic.
It will fit on the standard carbon fiber gudgeons as used on the F-32 and F-33, while the only change needed on an F-31 (with transom hung rudder) will be replacing the stainless steel transom brackets with custom CNC machined aluminum brackets, which also incorporate high performance plastic bushes. Tiller stub is designed so that just about any tiller end can be adapted and bolted in place.
Standard finish is a white gelcoat, but a clear exposed carbon fiber finish will be optional.
The prototype blade was made last year for Pete Pattulo's F-33R, who wanted a deeper and more performance orientated blade. Pete's original F-33 rudder case sleeve was modified at Farrier Marine in New Zealand to suit the new blade, and then air freighted back to Pete in time for the 2007 Miami-Key Largo Race. Pete reported back:
Ian,
The rudder is working great!! It was like going from a car with really bad/sloppy power steering to a sports car with precision steering. We've now had up all the fore sails and the helm is perfect and balanced in all configurations. We were first to finish on the Miami to Key Largo race!
Thanks again! - Pete
In the past ready made production rudders have always been a problem, as they are hard to make, and frequently the final shape left much to be desired, with the join seam only 'so so', while rudders were frequently thicker than they should be, or the blade was warped, or halves were misaligned, while the metal cases were prone to both corrosion and fatigue. The result was always something that would do, rather than something to be proud of.
However a new manufacturing method has been developed at Farrier Marine and the blades are easily the best I have ever made or seen. The substantial molds have been CNC machined for a perfect shape, and the rudder halves are aligned perfectly with six stainless steel alignment pins in special bushes embedded in the mold and placed accurately while CNC machining.
Production rudders are normally made in two halves and then joined together from the outside, but alignment and finished thickness has always been hard to control this way, as was straightness. However these new rudders are being joined from the inside, while the assembled molds are being held straight, at the correct thickness, and in perfect alignment. The final shape is thus virtually seamless, straight, or as near perfect as one can get.
The case has also been further developed, due to the fit of the blade in the case being so important for 'feel' and ease of use. Too tight and one cannot raise or lower blade easily, too loose and the helm will be spongy due to movement of the blade in the case. Cases are commonly made to a fixed size, and then lined with a marine carpet, but if fit is not exactly right, or carpet too thick, it will never work well. Making the exact size has always been difficult, and thus a fully adjustable 'double molded' case has now been developed, with a very thin synthetic fabric being used as a liner.
Width is adjusted by adding or subtracting shims each side of a polyethylene aft end strip (the case comes pre fitted with shims each side), while fore and aft length can be adjusted by simply tightening or loosening three nuts on the aft case edge, which will move the end strip forward or aft. It can also be angled slightly if need be to adjust balance area. Rudder blade fit can then be perfectly optimized, while the polyethylene strip is gentle on the rudder trailing edge.
Availability:
Blades are being produced now, while the case molds are in the final stages, and will be ready to go in April. The all carbon blade price will be US$2400, while case complete with tiller stub will be US$1500. The aluminum transom brackets if required will be an additional US$95 a pair, and will bolt on using the same bolt holes as existing stainless steel brackets. Deposits (US$500) are now being accepted and the first deliveries should start in late April.