Facing: Dee Smith in USA-7 off to a good start last November during the 2.4mR Worlds at Davis Island YC in Florida. Left – clockwise from top: maximum concentration while opening up a nice scenario astern during the 2022 Worlds; where once there were bulkheads, now there are only hollowed-out ring-frames; custom titanium stem fitting with integral headstay roller – note the bunched-up extra sailcloth which is then released downwind; powerful jib for the Tampa Bay chop but still able to be flattened out using a full range of sheeting controls more typical of a much larger one-design; max height forestay attachment – length is not limited but is naturally constrained by a maximum luff length for class jibs
My sail programme is now into the
seventh season. Quantum have been in my corner for all this time and are very easy to work with. Also my old friends at Dimen- sion Sailcloth helped me a lot. I obviously wanted sails to match the best mast and boat configuration, not the other way around. You get the best package this way. The last thing we did before the worlds
was add a bit of luff curve to our jib designs to exploit the extra headstay tension we now have. That worked out well. A few things on boat configuration…
Shroud base was minimum width, spread- ers the same and jib leads 3D adjustable, as on a TP52. Yes, I stole that one. Come the worlds and the new mast,
extra lead, improved sheeting precision and excellent sails gave me height at the same speed or more speed at same height. Then we come to the rating. In the 2.4m
Open Class you have to float in a tank to establish the rated length of the boat. My boat measured short and also weighed in at 255kg – 1kg over the minimum. But I left the weight alone which allowed me to increase E (mainsail foot) by 17mm. Which also gave me bigger girths! Further, there is no maximum mid-foot
cockpit. I always felt the splash guard slowed the boat every time a wave hit it, adding windage and messing up flow over the jib. With a smaller breakwater further aft, the wave has a chance to leave the boat naturally and so not slow it as much. Mast development took off in the class
in 2015. I always felt the standard Super Spars 2.4 mast was too soft, but the exist- ing alternative option was heavy which cost righting moment. So I asked Super Spars to build me some experimental tubes with new custom tapers… My premise was to leave the metal in
the tube for stiffness and take weight out elsewhere. I also wanted the headstay to be as tight as possible. Keelboats like head- stay tension, higher and faster in a breeze. No way round that one! Starting at the base of the mast, we put in
a Star boat-style heel-track to allow the rig to go forward downwind above the deck. This let us fix the mast at the deck (no gate slot) to shorten the panel span, meaning less bend aka more headstay tension. Then my lowers, made of Spectra, set just aft of the cap shrouds, and adjustable,
which effectively made them into check- stays, locking the rig at the spreader and again shortening the panel span – so less mast bend for the same backstay tension. A new custom mast crane was made in carbon, attached to the tube using tita- nium fittings. The fixed in-line spreaders were angled down to reduce windage upwind, set on a carbon spreader bar, also helping control bend at mid-height. Rock- solid Spectra SK99 is employed for head- stay, backstay and all halyards. To get the jib higher I put the headstay
through the upper hole of the halyard block spliced around a titanium bolt. This also helped to lengthen the luff length. Even with the heavier tube the new mast
is minimum weight, close to minimum tip weight… and stiff. It gives me very accurate sail control in all conditions. Even though the 2.4mR rule allows an
adjustable headstay this does not allow us to maximise the sail dimensions. So I went to a fixed headstay (at 4,190mm). The finished boat is very balanced across all heel angles so there is no reason to change the balance point via the sailplan.
dimension in the Open 2.4s, so now I could drop the boom while keeping the large foot. We then went old school and added a flattening reef so we can make the foot extra long for light air but still sheet well in a breeze. Another way I added sail area was with a tricksy jib-foot. As mentioned, the rule does not measure luff length. So we added luff length at the bottom of the jib. Upwind, pull on the jib cunningham and sail away, downwind let the cunning- ham go and the sail gets bigger. I figure about 0.5m2
bigger than standard. The result was a boat that in the light
had more sail area and less wetted sur- face… And in the breeze it has more right- ing moment and less drag. The rig and sail controls gave me more options to balance the boat out and sail higher when needed. The races themselves generally went
well… the single failure was the one line that I did not replace, when the vang strop to the mast step broke. Lesson there. Our final scorecard: 3,1,1,1,1,1,[3] – so
worth the effort. Needless to say, the boat sold right after the final race. Now just gotta do it all over again.
SEAHORSE 55 q
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