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Fitting-Out the Hulls
Photographs and comment on fitting out the hulls. Here is information on making cool boxes, creating water-tight
compartments and capping the bulkhead openings.
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A cool box is required to act as a refigerator. The design principles behind this cool box are covered in this article. A cool box to act as a freezer will also be constructed. The reasons for these refrigeration choices are given in this part of the website. The cool box is designed to use the maximum available volume (while having vertical walls) beneath the forward bunk in the starboard hull. The box is built out of 9mm plywood panels joined together using panel pins and epoxy. Insulation is Polyisocyanurate foam, often referred to as "PIR", "polyiso" or just "iso". The inspiration for the construction details shown here is Don Casey's excellent book, "This Old Boat". Top of Page 
Once the bevel is cut, the final sheets of insulation can be added. This adds another 12mm of PIR foam. These have a flat top since they will form the mating surfaces used to seal the box when the lid is down. These sheets will also be glassed on one side to give the inside linings of the box. In the areas where there will be battens, used to create internal compartments, the insulation is scraped away behind the batten and replaced with wooden strips of the same thickness as the insulation; this is to ensure that screws passing through the cool box lining have something to bite on other than Polyisocyanurate foam. All battens are epoxied to prevent absorption of moisture. Top of Page 
The lid is glassed with a 3-layer laminate of epoxy resin and a lightweight woven cloth of 165 gm/sq m. The lightness of the cloth ensures that it turns corners easily, closely following the shape of the lid. The epoxy is encouraged to bleed out onto the flat surface on which the lid rests .... Top of Page 
To give an airtight fit, the bottom of the lid will sit on a rubber seal glued to the flat top of the last insulation
panels fitted and the lip of the lid will sit on a second rubber seal glued to the top of the box. To ensure a good
mating between these surfaces a generous bead of thickened epoxy is applied over both of the boxes' mating
surfaces and cling film dropped over the whole bevel.
Top of Page 
In parallel with all this work on the refrigerator, work on the inside of the hulls has also started. Behind bulkhead No. 4, in the starboard hull, is the space where the freezer is going to go. Behind that is a locker - one can just make out that the central section is a lid which lifts out to give access below. Behind that, beyond bulkhead No. 6, is a sealed compartment with a watertight inspection hatch (tracked down on the Internet under the name of "deck plate"). Beyond the transom bulkead is another sealed compartment; the large inspection hatch gives access to the bolts which secure the rudder stock bearing. All inspection hatches are bedded down with silicone sealant. Initially, the screws fastening the deck plate to the plywood are finger tight; when the silicone has cured thus creating a gasket, the screws are tightened making a watertight seal.
There are 5 watertight compartments in each hull: two at the stern,
two at the bow and one under the cabin sole. The considerable buoyancy provided by these compartments, together with their fore and aft
location, make for a dry and seakindly boat unlikely to founder.
Top of Page 
After the bevel of the box is glassed, the fridge is painted with a two-part polyurethane paint. This smells horrible and is no doubt highly toxic but dries to an extremely hard glossy finish. Two coats of undercoat were followed by two top coats. Top of Page 
With the fridge closed, the starboard forecabin can be used as a large single bunk (42" wide at the galley end). The bunk matress will provide further insulation. Top of Page 
The edges of the bulkheads are being capped with strips of ash. The plywood edge of the bulkhead fits in a groove in the ash, cut with a router. The router is also used to round off the edges of the capping. The corner pieces of capping are cut with a bandsaw, routed to create the groove and then sanded to the same profile as the straight pieces. Top of Page 
Richard working on the forward steps in the port hull. These are a departure from the Plans and give access to a cabin, also not in the Plans.
In the Plans this area
is divided horizontally to give a sail locker, reached from above via a deck hatch, and a storage area, reached via the heads.
To give access to the new cabin, other than going through the heads, I have reduced the length of the heads compartment by 500mm and put in another,
bulkhead, without an opening, between the heads and the cabin. With this arrangement one loses a small amount of bridgedeck seating to
give access to the steps. There are drawbacks to my modification but having another cabin will, I believe, more than make up for them.
Top of Page 
The refrigerator circuit is connected up as shown. The thick wires (4 sq mm) are to the condensing unit and will ensure that any voltage drop when the motor is running is under 1%. All wiring is multi-strand, tinned marine cable. Fixings are ring terminals protected by adhesive-lined heatshrink. Details of the electrical wiring and wiring diagrams can be seen in this document. Jump leads are provided, using push-on terminals, in the power supply to the condensing unit; this allows the circuit to be broken and a meter inserted to measure the power consumption of the fridge. Top of Page 
The decision was taken to make a feature of the stringers and panel between them with extra insulation (12mm of PIR board) faced with 4mm thick flexible ply. The insulation was fixed to the hull with contact adhesive, which was also used to fix the flexible ply to the insulation. Any gaps were filled with epoxy. After sanding the panelling was painted. Top of Page 
... and this is the result for a fore cabin. Note that a couple of panels each side in the hull's nose are missing. This is to allow enough room around the front beam for glassing it to the hull. The front beam is one of the main cross members that will eventually join both hulls together; this area will be insulated and panelled after this is done. A small part of the hull in the aft cabins have also been left unpanelled to facilitate the fitting of the aft beam. Top of Page 
All lights now fitted to both hulls. In each hull there are 8 2.4W LED downlights and 5 2.8W LED spotlights. The spotlights came with MR16 hologen bulbs and
had to be changed to LEDs. LEDs from two different suppliers caused electromagnetic interference with my radio tuned to an FM station (94.3MHz). The cause is
was the switched-mode regulator, common to most LED bulbs. Here is a
forum thread which explains the phenomenon.
EMI can easily be prevented but many manufacturers cut corners to shave a penny off the cost price. I eventually found bulbs which are EMI free
here.
Top of Page 
Here is the Airhead composting lavatory in the heads compartment. The hose will go to a mushroom vent on the deck, which can be closed from the outside in heavy weather, when at sea. In the moulding on the end of the hose is a small extractor fan which will draw air over the internal compost heap, providing oxygen for the aerobic bacteria. The urine is collected in the bottle at the front from two holes in the front of the bowl - one is visible. Behind the urine holes is a door which can be opened by a lever on the other side of the lavatory, to deposit the faeces onto the compost heap. Instead of flushing one turns the handle to bury the faeces in the compost. Before using, the lavatory is primed with a small amount of compost from the garden centre - cocoa shells (a by product of the chocolate industry) is ideal. Here are the reasons why a composting lavatory was chosen. Top of Page 
The galley is now under construction. This photograph shows the space under the starboard worktop divided into what will become 3 cupboards and 1 drawer unit.
The dividers hang off the hull secured by fibreglass tape and epoxy. There are no legs down to the cabin sole, to support the storage units, which means
we have a good "toe kick" free of obstruction.
Top of Page 
Shown here is the Morco D61B LPG water heater. For reasons why I went with LPG see here. The flue is twin-walled for passing through the deck without overheating the plywood. The cowl sits on top of the flue and can be removed in bad weather - I will have to fashion a blanking plate to put in its place to seal the flue. I did consider a balanced flue, but the boiler was a lot more expensive and required a 240V supply to drive a fan. A balanced flue ensures complete combustion of the LPG with no carbon monoxide(CO) being generated. However, provided there is adequate ventilation around the boiler this is not a problem. For this reason, I have sited the Morco in an area open to the bridgedeck rather than in the heads. Also, the boiler will only be in use for short periods, so any CO generated will disipate quickly. In addition, I will be getting a CO alarm! There is a school of thought that only balanced flue (or room sealed) appliances can be instaled on a new build boat. Many think this a requirement of the Boat Safety Scheme. However, my research, written up in my plumbing details document,shows that this is not so. Top of Page 
The final set of steps is installed, leading down into the port hull giving access to the Heads and a double aft cabin. On the left will be a small cupboard, the top of which will be level with the bridgedeck floor. The curved nature of this cupboard is an example of how we are trying to avoid any sharp corners and thereby minimising injuries caused by losing one footing as the boat lurches in rough seas. Hand holds will be added later. Top of Page 
Here the cupboard has been swung open exposing some rather untidy electircal wiring - another item for my "to do" list! Top of Page 
This photograph shows the gas supply to the hob. The gas supply from the gas locker is 3/8ths inch copper pipe which has to couple to a 5/16ths inch pipe on the Smev hob. The Boat Safety Scheme mandates compression fittings for joining together pipework, although all of the pipe run has to be accessible so all fittings can be tightened up if necessary. Flexible gas pipe is acceptable for joining an appliance to the boat's supply. For more information see the BSS Essential Guide to LPG installations. Top of Page 
Bunks, by definition, do not have a bedside table. Most cabins provide one using a shelf with a large fiddle. I have often found these irritating since they are too high to see into, you have probably forgotten what you put there and have to search for lost objects by touch. A hot wire strip heater allows you to bend acrylic and therefore make all sorts of useful containers .... Top of Page 
... a pull-out tray for the fridge.
Top of Page 
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The box has 100mm on insulation, installed in overlapping sheets of 25mm. The sheets are glued to each other using epoxy.
A bevel then has to be cut; one starts off with a hacksaw blade and then continues with a crosscut saw as soon as there is room
to do so. The crosscut saw makes it easier to cut a symmetrical and even bevel.
Top of Page 
A bevel is cut on the lid to match the one on the box. This is easier to do than for the box since only the crosscut saw is
needed. The thickness of insulation is less on the lid (100mm) than on the box (112mm) for three reasons:
Top of Page
.... to give a lip which will mate with the top of the box to seal it when the lid is closed. Top of Page 
The lid is then fitted and a heavy weight used to squeeze the epoxy along the mating surfaces, up the bevel and into any gaps. When the epoxy has hardened but not fully cured, remove the lid, peel off the cling film and trim away excess epoxy. Sand when cured. This procedure might have to be repeated to get a good fit - it was in this case. The sides of the bevel can then be faired using epoxy mixed with a low-density, microballooned-based filler (this is more easily sanded than epoxy mixed with colloidal silica). Top of Page 
Here Richard is "joggling" to get the shape of the panel to seal off the galley end of the daggerboard case. The other end will be open, thus creating a small hanging cupboard in the aft double cabin. Top of Page 
The fridge is finished, but not yet operational- it just needs to be connected up. The double seals are closed-cell expanded neoprene, glued to the lid with waterproof contact adhesive. The evaporator plate is actually an ice box. The copper pipework containing the refigerant requires a hole of about 1.25 inches to be drilled all the way throught the side of the box. The pipes are not that wide, but the nuts that connect the pipes to the condensing unit are. The hole is filled with expanding urethane foam to seal and insulate. Top of Page 
Back to the hull. The daggerboard case side panel is fitted. The bulkhead which will contain the door to the starboard aft cabin has been shaped and
fitted to its frame.
Top of Page 
Mac at work on the last bulkhead, trimming the door opening to the heads compartment. It is one of the biggest bulkheads and had to be made out of 2 sheets of plywood, necessitating a scarf joint. We have put in 18 in all! An unbelievable number. They are:
Top of Page 
The first bit of electrical control equipment gets installed: a digital thermostat for the fridge and a distribution panel providing a 12V supply for the fridge's condensing unit. Both are fitted into the outer walls of the starboard aft cabin. Underneath the distribution panel will be a chart table, on the bridgedeck. Top of Page 
The freezer is now finished and insalled under the bunk in the aft cabin in the starboard hull. Since the building method is the same as for the freezer, you are spared a blow-by-blow account of its construction! However, note the evaporator, which is a big plate rather than a small box - necessary to hold the temperature at a much lower value than for the refrigerator - approximately -18degC. The big plate also needs a more powerful DC condensing unit. The useable freezer volume is larger than the refrigerator (approx. 74L cf. 64L) which is why it is under the larger aft bunk rather than the smaller forward bunk. The relative sizes reflects a personal preference. The freezer also has over 6" of insulation, making the external volume much bigger than the refrigerator. Top of Page 
This is the result for an aft cabin...
Top of Page 
By this stage, the DC wiring in the starboard hull is fitted, apart from some reading lights. The AC ring main is also in place but not yet connected to the inverter. This picture shows wiring for the aft cabin lights in the port hull. One can see the 2 down-lights and wiring for 2 reading lights. The down-lights are SMD LEDs giving 140 lumens for 2.4W - equivalent to a 10W halogen bulb. The wiring is led through holes in the carlins and then either side of the bulkhead in trunking. Top of Page 
This photo shows me using a power tool powered from a 230V socket in the port forecabin. We now have AC power throughout - which comes in useful since we no longer need extension leads snaking all over the place. The AC power is provided by a shore power connection, through the Combi Inverter/Charger - the inverter is not being used, so the batteries are not being drained. The electrical system is described in this document. Top of Page 
The composting lavatory has been set up in a corner of the polytunnel, replacing the chemical Porta Potti we had been using before. The extractor fan has been connected to the boat's batteries, via the DC distribution panel; unfortunately it vents into the polytunnel - if it gets too smelly I will have to cut a hole in the polytunnel plastic, so it can vent outside. UPDATE:it did get a bit smelly, especially after a new "deposit", and it now vents ouside the polytunnel! Note the coffee filter papers. Their purpose is to recieve the "donation" prior to openning the trap door to add it to the compost heap. The word "donation" is the word coyly used by Airhead in its instructions manual to refer to .... well, we can all guess what it refers to. You don't have to use the coffee filters, you could just open the trap door to begin with and let gravity do its work, the pan might not be quite as clean afterwards but the design is good enough to ensure good results no matter which method is chosen. Using it in the boatshed does give us the opportunity to sort out any teething problems before installing in on the boat. I have written an article describing how we adapted to using the composting lavatory here. This gives more information on how it works, the problems I had commissioning it, how all of us felt about using it and an aide-memoire for occasional users. Please note the very smart screen we are using to give people some privacy. It is an original painting by Mac covering all three hinged panels, and adds a touch of class to the boat shed. Top of Page 
The other side of the galley also hangs off the hull, thus giving a toe kick. It is rounded at the end of the steps, so there are no sharp edges to stumble into when under way. There are more dividers here since the fridge and freezer condensing units are boxed in, to separate them from the cupboards. Care is taken to allow a free flow of air to each condensing unit. The mast beam is also secured underneath this worktop, on the other side of the flexible-ply. This means there are only two usable cupboards on this side of the galley, underneath the work top - there will be more above. Top of Page 
The draw unit problem is: how to decide upon the height of each drawer? One could have each drawer the same size, but drawer units look better if lower drawers
are deeper than higher ones. It was decided to base the drawer sizes on root rectangles, part of a visually pleasing system of symmetry which gives drawers
of differing heights - a method which is used widely in furniture design. For a full explanation I have a section on the design of drawer units in my document
construction_details.pdf. This links to a spreadsheet for calculating
the height of drawers for a given size of drawer unit - root_rectangles.xlsx.
Top of Page 
The most complicated cuboard is the one in the starboard aft cabin. It consists of a vanity unit at the top and a wide but shallow cupboard underneath. It is complicated because the whole cupboard is designed to swing open to give access to the electircs control panel behind. Top of Page 
All cupboards and drawers are latched using elbow catches which are accessed through teak rings using one's finger.
This sort of catch, inside the cupboard or drawer, avoids knobs and handles which can cause bruises and sheer off if stumbled against in rough seas.
Top of Page 
In the heads, in the port hull, we have a grey water tank. This will take waste from both sinks and from the "bilge" pump. The main job of the pump is remove waste water from the shower sump but it can also remove water from elsewhere via a flexible hose - a diverter valve switches between the 2 uses. See my plumbing details documentfor more details. The grey water tank can hold up to 90L before it needs to be emptied, a useful capability if dried out on a pristine beach. The photograph shows the inside of the tank, glassed and epoxied, with the drain hole at the bottom and the lid, which will cap it, propped up against the bulkhead, containing an inspection hatch and three drain connections. Tony Moyes, on his Sagitta, has a grey water tank which can be used as a fresh water tank if required. This sounds like a good idea but it is a complication too far for me at this time. Top of Page 
.... such as transparent bedside tables, or .... Top of Page 
Owen laying a "teak effect" sole in the galley. Traditionally, the floor consists of 4mm thick strips or teak separated by thin strips of a white wood such as holly. In our case we are using iroko and filling the gaps with epoxy mixed with a white pigment. The #10 screws serve as spacers, giving about 5mm between the strips, and the washers hold the strips in place while the epoxy binding them to the plywood floor sets. The steps will have a similar treatment. The first piece of iroko is in place on the top step; it has an "L" shaped section so that the edge of the step is also covered with iroko as well as the upper surface. The technique is described in the excellent book, The Gougeon Brothers on Boat Construction. Top of Page 
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