Article 7 - Fitting out the Hull Shell
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This article is as printed in Sailing New Zealand magazine November 2000.

The old 80/20 rule definitely holds true in yacht construction. We managed to do 80% of the job by building three hulls and decks in a little over 4 weeks, the final 20% of each boat seems to take forever…

Attaching the Decks
To reduce the frontal area of the hull above the water, the topsides have been made closer to vertical than is normal in the class. The desired effect of this is to reduce the wave drag encountered when sailing upwind in choppy conditions. A conflicting aim was to make the boat as wide as the rules allow at deck level to give maximum righting moment to the crew while trapezing. The solution to this problem was to add small "gunnale wings" extending about 120mm from the sheer to bring the hull to maximum width. The gunnales were moulded as part of the hull shell, and are 20mm thick in a very light 60kg/m3 foam. On top of this the 10mm deck has been added that is made from a more resilient 80kg/m3 foam. The joint between the decks and hull is a pretty simple one; just mix up a heap of epoxy glue, stick it down the gunnale and then sit the deck on top, clamp it in place (heaps of clamps), remove the excess glue, wait overnight and you're done. When joined together the gunnales are 30mm thick and definitely strong enough to take the weight of a 100kg crew bouncing down the sides. The exposed foam edges were then rounded off with a router, and covered in two layers of 400g double bias cloth. We reckon this will be grunty enough, however the proof will be if we can survive a 40 boat startline in a fresh Wellington southerly.

Transom and Rudder Fittings
The transom was constructed with a lightweight 60g foam with a piece of thin walled "paddle tube" glued on top. The top 100mm of my garage broom was sacrificed and ended up being glued into the middle of the tube where the top gudgeon is bolted through. A compression strut was taken from the top gudgeon to the false floor to take the forward load from the rudder. The bottom gudgeon was a bit more a problem. We didn't want to cut any holes in the false floor, so were not able to through bolt through the transom. The solution was to glue a pre-bolted plywood insert into the transom with the bolt heads glued in place and then add a couple of layers of carbon to hold it all together. The mainsheet bridle for stern sheeting is attached to a strengthened area of the transom inside the deck line to allow the skipped to get right to the back of the boat to help hold the nose up.

This is a bit of a diversion from the original plan, in this boat we are deck-stepping the mast rather than sitting it on the false floor. Current skiff rig designs are based around the concept of locking the rig in place from the hounds down, and using a more flexible topmast to automatically depower in the gusts. This new mast is being designed with long spreaders, D1 stays to the spreader base, and check stays to the gooseneck instead of a mast ram. Deck stepping the mast places ½ metre of mast weight into the measured hull weight reducing overall sailing weight, but more importantly it reduces the amount of section down low that can bend. The mast is stepped at deck height on top of a 600mm stump made of an old broken mast tube which has been glued into the main bulkhead.

The spar itself will be from Tim Willetts masts. Tim has developed a mast suited to my style of sailing, which is for a maximum of automatic response from the rig, with limited on the water adjustment required. This mast is a contrast to the other new Willetts Javelin section this season being used by Geoff Wilding and ex National champion Craig Gilberd. In this double spreader section everything is adjustable from inside the boat, including an additional set of check stays to the masthead. Both these masts are incredibly light, and will weigh in at around 4.5kg for a 7.5m long section. Tim himself has recently got back into Javelins and is developing a more radical deck stepped over-rotating mini wing section.

Whilst the top three boats at last seasons nationals all used sails from different sailmakers we felt that there was only one choice. Ken Fyfe of Fyfe Sails makes really fast skiffs sails, has many years of experience, will always work with new ideas and can help tune up the boat. In our case we are developing a boat that want to be able to drive fast in the higher wind ranges. To do this we have reduced our mast height by around 200mm to lower the centre of effort (and boom height), and will be getting a mainsail sail designed with a slightly longer foot length giving a lower aspect ratio than is the current trend in the class. We hope this will give us less drag, less heel moment and more forward drive, and should also reduce the tendency of this fine hull to nosedive when pushed hard. The gennaker is a pretty simple choice, with windward/leeward courses becoming predominant the sail is cut bigger and optimised for running deep.

Running Rigging
Many of the systems in this boat are configured similarly to my current hull. Running rigging runs around the cockpit, not though the middle, which keep things clear for tacking and gybing. We have removed the central mainsheet bridle to further open up the centre of the boat and allow crew movements in light weather to be subtler without having to work around the mainsheet. The mainsheet itself will run from the transom into the boom, where it will have a 2:1 purchase before exiting at the mast. Through a ratchet block on the floor and then into a tube/foot stop on the floor back to the centre of the boat. The gennaker halyard also runs through a tube to the centre of the boat. On a false floored boat in particular there is always a tendency to step on lines at the wrong time, putting them in a tube is a little bit of insurance to make this impossible. The gennaker sheets are run under the decks (so the skipper can't sit on them) and back through an exit sheave in the side decks. Lots of advantages here, but basically, in a messy gybe you can only grab the correct end of the sheet as the other is outside the hull.

Hitting the Water
All going to plan the mast will have been stepped over Labour Weekend, we will finally choosen a sexy paint colour and will be sailing before you read this…