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Constructing the Daggerboards & Cases
The construction of the daggerboard cases and the fitting of the cases
to the hulls. The daggerboards have the same function as a keel, centre board or lee boards on a monohull - they provide lateral resistance
so that a boat is not pushed too much to leeward when the wind is not behind it.
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These digrams show the position of a daggerboard in each hull. In both diagrams the dagger board is shown lowered. In the bottom diagram one can see how the daggerboard is controlled. There is a need for both an uphaul and a downhaul. Out of the boat a daggerboard is heavy - even made of Western Red Cedar, 2 people are required to lift it; the uphaul therefore requires some mechanical advantage using pulleys and a winch, when being retracted by one person. When lowered the buoyancy is such that a downhaul is required to stop the daggerboard riding up in its case. When the daggerboards are lowered the Eclipse has a draft of 1.7m giving it excellent windward performance; when they are raised the draft is only 0.5m which gives excellent creek-crawling (or gunkholing) capability. Top of Page 
After gluing and shaping, but before profiling. The daggerboard has the correct shape, when looked at from the side, but not yet an aerofoil section. Top of Page 
This is what the slots are for! Note that the slot for the sheave has to go all the way through, which it doesn't yet.
Top of Page 
The router is again used to cut down to the depths required to give an aerofoil profile. The cuts are parallel to the long edges of the board. An electric plane is then used to remove the wood down to the bottom of each cut. Top of Page 
The daggerboards are now back in the boatshed The slots have had three coats of epoxy to waterproof them. The pulleys (sheave plus rod) have now been epoxied into position and the rod slots filled-up with wooden inserts. The blue plastic is to protect the pulleys from the epoxy while the daggerboards are being sheathed with 600 g/sq m glass cloth. Top of Page 
The flat side panels of the daggerboard case need to be bent around the daggerboard. This is achieved using nose and tail pieces laminated using the daggerboard itself as the mould. Note that the daggerboards are now glassed. Top of Page 
The daggerboard cases assembled around the daggerboard. The "Heath Robinson" arrangement of clamps, gaffer tape, rope and wedges is our
attempt to hold it all aligned while the thickened epoxy goes off; fine engineering it isn't, but Richard is clearly proud of it - and so am I!
Top of Page 
Well, we did get the daggerboard out of its case. The daggerboard case is surprisingly heavy, which is reassuring but does make man-handling the combination of daggerboard plus case hard work. A very large hole has now been cut in the starboard hull to receive a daggerboard case. Richard is so pleased with his handiwork that he is busy sketching it - actually making a note of the dimensions so that the one in the port hull is easier to do. Top of Page 
The cases are now installed with plenty of reinforcement. There are 6 layers of 600 g/sq m cloth along the inside of the case and tucked around the ends. The floors (i.e. sole supports) are fitted afterwards and epoxied to the cases. The floors are also supported by strips of cloth with the weave filled with thickened epoxy. Mini bulkheads connect the case to the hull. Epoxy has also been dribbled down the outside of the cases in several applications to provide a thick fillet joining case to hull. The idea is that if the board does hit a rock, or a container, the trailing edge of the board will give before the case. The daggerboard case is the only through-hull fitting below the waterline, so it is important to make it watertight in the event of a board hitting something. Top of Page 
A finished daggerboard - finished, that is, apart from the final paint job. The sheaves spin nice and freely once the protecting blue plastic has been
removed.
Top of Page |
Gluing together thirteen 12 foot lengths of 4" by 1.5" timber requires a lot of clamps and heavy weights in the middle to stop bowing. Western Red Cedar was chosen because of its lightness, strength and high natural resistance to decay. The daggerboards were made by Owenin his workshop. Top of Page 
Before profiling, slots are cut halfway through the daggerboards using a router with fences clamped to the boards. The big slot is for the sheave and the little one for the rod. The router bit needs to extend below the router base by about 4", so a long bit is required. Top of Page 
To complete the slot a hole is drilled right through the board. A trimming bit is then inserted from the other side. The bearing will use the half-slot
already cut as a template while the router is used to complete the slot. Very cunning Owen!
Top of Page 
As you can see, planing away the excess wood creates a lot of sawdust!
Top of Page 
The laminating table for the flat panel sides of a daggerboard case. The waste pipe halves provide the groove for the uphaul rope. Two layers
of 600 g/sq m biaxial cloth are laminated together using 3 applications of resin - scoring down the middle, before the resin gets too hard,
separates the 2 halves. The resin will not stick to the formica surface (or any high-pressure laminate (HPL) sheet with a Melamine surface).
The waste pipe though was not as obliging.
Top of Page 
The daggerboard and daggerboard case bits & pieces ready for assembling. These are: the daggerboard (wrapped with thin rope of diameter 3mm - acting as a spacer); two side panels, one nose cone and two tail pieces Top of Page 
Laminating the side panels for daggerboard 2. Actually, this is the second time for this. The waste pipe halves did not stick to the epoxy when laminating the first pair of side panels but did second time around. The waste pipe was obviously coated with something which acted like a release agent; when the side panels were extracted from the laminating table the coating was removed also. We had to throw the second set of side panels away! With the second pair of waste pipe halves we took no chances, liberally coating them with vaseline. Notice the first daggerboard case in the background. This is now finished and curing prior to the daggerboard being removed - we hope! Top of Page 
The daggerboard makes quite a nice snug fit in the hull - a pleasing result but the best part of a day's work for two of us. Trying to do this by oneself would have been back-breaking work. The 18mm plywood & G-clamps contraption is a jig to hold the daggerboard case at the correct angle while glassing it into position. The case is deliberately overlong to ensure that it protrudes above the coachroof - it will be cut flush with the coachroof later. Top of Page 
On the outside, the daggerboard case has been cut flush with the hull, sanded smooth and then filled with thickened epoxy. It has then been glassed with a strip of 600 g/sq m cloth which bridges the join between the hull and the case. In this photo it has yet to be sanded and painted with the same copper/epoxy mix used below the waterline. Top of Page 
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