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Iain Oughtred’s Caledonia Yawl is proving to be a popular design for us. And why not? It is an attractive double-ended lapstrake sailboat that is easily rigged and sailed single-handed yet can accommodate the better part of a Cub Scout troop and the dog.

We recently received a commission for the newest release of this design, the seven-strake version. It has numerous enhancements as wells as a slightly wider beam than the four strake version we have built previously. The customer prefers the sloop rig over the lug yawl, which eliminates the mizzen mast, yard, boom and boomkin, and can use a more conventional straight tiller.

The CY is based on the traditional lines of Norwegian and Shetland open boats. She is seaworthy and comfortable, with a spacious interior. She is capable of carrying large loads yet light enough to be easily handled in the water or on a trailer. The beaching rudder and easily raised centerboard allow her to navigate shallow waters under sail or by paddle or oar. Numerous configurations for the interior allow each boat to be built to the unique requirements of the customer.

We got started by setting up the ladder frame at a convenient working height for lofting the boat. Lofting on the shop floor is much too hard on the back and knees. Due to other projects in the shop, we set up the lofting in the side yard where we have plenty of room.

Lofting is the process of converting the scale drawings from the architect to full-size using the offsets (measurements) provided with the plans. This allows us to make the necessary station molds that establish the shape of the form that the hull is built on, and the patterns that will be used to build the interior components. Lofting also ensures that the hull components will fit together correctly.

Iain provides full size paper patterns that can be used instead of lofting the boat, however we have found that the time spent lofting the boat is well spent, since it allows us to work out the shapes of components without resorting to the less efficient “cut and fit” method.

We laid out sheets of particle board to create a long 24’ x 4’ surface. We then nailed sheets of 1/8” door skin painted flat white to the particle board. We then draw a grid to create the three views we will need – the profile, half-breadths, and body plan. The profile view is the hull seen from the side, the half-breadths is seen from above, and the body plan is seen from the bow and stern.

We then created a series of tick sticks that contain the measurements from the chart of offsets provided with the plans. We use these sticks to mark the location of the offsets on the grid.

Then, using a stiff batten, we connect the dots and create a fair curve. Battens are best made from soft woods; Spruce and Cedar are good choices. If the batten is rectangular rather than square in cross-section, it can be used for a wider range of bend radius. Always use the stiffest batten possible to ensure the batten doesn't easily deflect, and give a false contour. Drill a hole in one end and hang them from a nail when not in use, otherwise they will deform over time. Sometimes I paint them black, which can help visualize the long sweeping curves.We do this for each set of measurements, comparing the resulting drawings with each other for consistency. Here we are showing the batten marking the position of station mold 1 on the body plan.

The next step will be to add more details to the lofting and create the station molds.

Since the weather can be unpredictable at this time of year, there are other things we can be working on: spec’ing the sail plans, procuring materials, and specifying colors. We have received the bulk of the plywood we’ll need, and are now getting in the other materials we’ll use – hardwood and softwood lumber, brass half-oval and flat stock, paint and rope. There is plenty to do!

We are getting into full swing on the construction of the boat. In the last few weeks we have made the station molds and set them up on the ladder frame.

Making the molds is an interesting operation. We take 3d nails and lay them along the station lines of the body plan. We then take a section of 1x6 pine and place it on top of the nails and give it a few good whacks with a mallet. This transfers the location of the 3d nails to the underside of the 1x6 pine. Using a batten, we draw a line connecting the indents, creating a fair curve representing the shape of the hull that station.

We then nail the 1x6 pine to a second piece of pine and cut both simultaneously on the bandsaw, This ensures the port and starboard sides of the mold are identical. The molds are usually made in several sections, so the process is repeated until the entire curve of all the stations are created. The sections of the mold are assembled into a whole, creating the shape of the hull at that station. A cross spall is added to each mold at the baseline. The location of this cross spall is critical, as it establishes the height of the mold on the ladder frame. This ensures the molds are all vertically aligned with each other.

We set up the ladder frame in the shop, making sure the rails are parallel, level and in the same plane as each other. The rails are spaced an appropriate distance apart based on the beam of the boat being constructed. To support the stems, cross members at the bow and stern are set at an angle. We transfer the location and angle of the stems from the lofting. We then stretch a string to mark the center line the length of the ladder frame.

Then we were ready to set up the molds. Using the lofting as a reference, we marked the locations of the molds on the rails. Then one by one we installed each mold aligning the center lines and ensuring they are level and plumb.

We decided to laminate the inner stems with 9 to 10 laminations of sapele. Using the same method with the 3d nails, we transfer the shape of the stems to two pieces of 2.7 mm door skin to make a pattern for each stem. We then trace the curve of the pattern on a piece of particle board. We glue and screw short sections of 2 x 4 every few inches along the curve. The laminations are bent around these blocks and clamps hold everything in place until the epoxy cures. Once well cured (about 24 hours) we plane the stems to thickness.

In the meantime we've milled up the material for the keelson. We have learned from experience to cut the centerboard slot in the keelson on the table saw before installing it on the ladder frame.

For aesthetics, we beveled the top edge of the keelson and inside face of the stems. Then the keelson and stems are installed on the ladder frame to form the backbone. The outer face of the backbone is beveled to accept the planking. All of this setup is time consuming, but well worth it in terms of easing construction going forward, but more importantly, to have a pleasing shape to the hull.

While glue is curing we are working on other items. We draw the shape of the rudder on the lofting. This helps us determine the location of the rudder and the rudder hardware so we can get it on order.

We also draw the centerboard trunk on the lofting. We make a pattern for the centerboard and place it on the lofting to make sure it fits well and that there is adequate clearance as the board moves up and down in the trunk.

We use the same 3d nail technique to make a pattern for the centerboard trunk. This is made from 9 mm okoume marine ply with sapele logs and spacers. This is glued in sections and set aside until ready for installation.

Once the backbone is set up and beveled we start making patterns for the strakes. We can hang a pair of strakes a day, so this seven strake boat will be planked in little over a week.

This photo shows that we still have the sheerstrake to hang.

We then bevel the garboard to accept the keel and stems. Climbing on top of the boat is the only way to reach it!

Unlike the inner stems, we choose to build up the outer stem from solid stock. Laminating the inner stems is practical because it is consistent in cross section whereas the outer stem varies considerably.

We marked the sections of the outer stem on the lofting and then using the same 3d nail transfer technique, made patterns for each section out of 2.7 mm door skin. By taping the sections together, and fitting them to the boat, we can be sure of an accurate fit before cutting stock.

We fit the keel to the boat, and cut a rough slot for the centerboard. Once the keel is installed and the epoxy is cured, we used a flush trim bit in a router to finish the slot.

At this point we were ready to turn over. This used to be a nail biting exercise as the two of us lifted her off the mold and turned her over. Since the operation was completely impractical when turning over the hull of the electric launch we built a few years ago, we installed two pairs of rollers in the roof trusses of the shop. With a loop of webbing around each pair of rollers, turning over a hull is now significantly easier on the back and the nerves. Our customer and some family members chose to come to the shop for the occasion, so we had some help, making it even easier.

The rest of these photos illustrate the process of getting her off the mold and turned over.

We picked up lumber to make the spars. We are fortunate to have easy access to Sitka Spruce. A small mill an hour from our shop brings logs down from Alaska and grades and mills the wood to our specifications. We usually buy 8/4 Sitka 6” wide and 20 ft long. This allows for minimal waste when used for oars and spars.

We spent one afternoon gluing up the mast, boom and yard halves. Later we will shape them from the rough straight four sides to tapered round sections. We will cover that in more detail when the time comes.

Once the boat was turned upright, the pace picked up. The centerboard trunk we made earlier was installed.

We then added the forward brace and trunk cap.

One day was "Floor Day", where we made all the floors, which strengthen the bottom of the boat as well as supporting the floorboards. We are halving the spacing of the floorboards so that we can use thinner material for the floorboards. Thinner floorboards are easier to bend into place and lighter and easier to handle when assembled into sections. Additional floors also better support the floorboards.

We fabricated and installed the deck beams and bulkheads. The aft bulkhead is full height to the deck, with an enclosed section on the starboard side and a motor well (as yet unbuilt) on the port side.

The forward bulkhead is only a partial bulkhead which will allow for storage under the forward deck.

Since you spent a lot of time waiting for epoxy to cure while building a glued lapstrake boat, you always need to have other projects in the works.

We turned our attention to the rudder, rudder head and centerboard. These are laminated from multiple thicknesses of plywood to yield the desired thickness. We have to run a couple of pieces through the planer to shave off a millimeter. No 5 mm stock on hand? No problem.

One pass through the planer on the 6 mm, and presto: 5 mm.

We use two methods for gluing up the pieces. The first method involves screwing the glued plywood sandwich to the workbench, but that means we later have to plug the holes.

We chose to use the second method -- vacuum bagging.

We installed a new surface on the bench, a piece of 3/4 melamine-faced particle board. We then placed the glued up plywood sandwich on the bench. We placed a 3 mm plastic sheet over it and sealed it around the perimeter using butyl tape, which is readily available from our local hardware store. Using a fitting that attaches to a compressor and creates a Venturi vacuum we suck the air from the work piece aiming for about 21 inches of vacuum. We allow about four hours for the parts to cure. During the winter the shop is much cooler and the cure time can double.

Before assembly, we shape one of the outer layers to the final shape using the pattern as a guide. The rest of the plies are rough-cut. After the epoxy cures, we use a flush trim bit to rout the rest of the parts to the final profile.

We picked up the King KB-910 trailer in mid August. These galvanized trailers are great for this area because they can be used in both fresh and salt water. The long tongue makes backing easier and helps keep the tow vehicle out of the water.

We’re working steadily on the interior. Fitting the floors, bulkheads and thwart risers is fussy work – it takes time to get the fit just right. We have to wait until we receive the Torqeedo motor before we fabricate the motor well, and we have to make the motor well before we install the decks.

Fairing the sheer is an important part of completing the hull. It has to be considered from several angles so that it looks right in all views. When planking the boat, we make the sheerstrake a little wide to allow for some modification. Here we have clamped a batten to the upper edge of the sheerstrake and we are getting ready to trim it to shape.

Before we go too far with the bulkheads and decks, we have to consider the porta potti. We ordered the shortest model available, since it has to fit under the forward deck. We still had to make a slight modification to the width of the forward bulkhead so that the porta potti could be stowed there. The photo illustrates the porta potti in place, as well as the side benches. They will be bolted to the underside of the center thwart and will rest on cleats at the aft end and the partial bulkhead forward.

This photo also shows the trim piece being glued to the sheer. This covers the end grain of the plywood which would otherwise be visible when varnished.

Next we glue on the inwale to strengthen the sheer. This takes all of our clamps! You can never have too many clamps.

Then it was time to stop and get ready for the boat show. Since we were delivering the Tirrik the day after the show ended, it had to be ready. We had made the decision to take the CY in whatever state it was in, as long as we could get it on the trailer. Here are a couple of pictures from the show – the Tirrik with her sails up, and the partially built CY. We brought along her partially made spars, centerboard and rudder. Visitors found it very interesting to see the partially completed boat and the beautifully finished one. The contrast between the two boats helped people have a better understanding of what it takes to build one.

The mast, yard and boom are ready for finishing. The centerboard is shaped and the lead insert is poured. The rudder trunk is assembled, the rudder blade is shaped, and the tiller is ready for finishing. The side benches and thwart knees are fitted, the motor well is finished, and the areas under the forward and aft compartments are ready for paint. The keel shoe has been fitted, as have the bilge runners and their half-oval bands. The rudder hardware has been cast, and is almost ready to install.

The brass shoe is 1/4" thick. It provides then best possible protection to the keel and skeg, which is perfect for beaching and trailering. The stems are protected with half-oval brass which is also 1/4" thick.

The bilge runners have 1/4" half-oval over their entire length. The fitting of this metal is labor-intensive, with all the rolling bevels and compound angles, but the protection makes it all worthwhile. It also adds about 35 lbs way down low on the boat.

The gunwale (guard) is built up of two layers, which combined with the three inwale layers, makes for a very stiff sheer. Add in the laminated frame (currently gluing up), and the bulkheads, and you have one very rigid hull. This is particularly nice on a rig which relies on shroud tension to keep the forestay tight.

We complicate the gunwale a bit by having it taper in height and width as it approaches the ends of the boat. If the gunwale is a constant cross-section it will appear to grow towards the ends of the boat. The hard way looks much better, and once you realize this, there really is no other way to do the job right.

The motor well take a bit of thought. We considered making the cutout in the hull as small as possible, but that would require ensuring that the propeller was in the vertical position when installing or removing the motor and that didn't seem like a good idea in a panic situation. So a pattern for the cutout was made which allows the prop to be in any position.

The diameter of the prop and length of the lower unit requires that the well be a few inches larger than Iain drew. The well is as small as is possible, with about 1/2" of clearance from the cutout to the well sides. The cutout was made as close to the keelson as practical.

Cutting out the well opening is a bit tense. The cutout is used as a plug when the motor is removed for sailing, so the saw cut needs to be accurate.

The edge of the cutout is vulnerable, so we epoxy on a layer of Dynel fabric to beef it up.

The motor fits well. We'll need to raise the forward edge of the well up an inch or so to get plenty of clearance between the aft deck and the bottom of the powerhead. No big deal and it will look nice, too. The long shaft gives plenty of clearance between the prop and the hull. The short shaft may have worked, but this removes all doubt.

There is a lot of prep work to get ready for undercoat. We are also doing a lot of sanding and filling, and epoxy coating of plywood end grain.

Before assembling the centerboard trunk and the rudder head, the interior surfaces are coated with graphite filled epoxy. This negates the need to paint these areas in the future, and protects against chafe in high wear areas. Note that the channel for the rudder control line is also coated with graphite filled epoxy.

We weight the centerboard by adding a lead disk. We cut a hole of the correct size near the bottom of the centerboard. We chamfer the edges of the hole and insert bronze ring nails to stabilize the lead plug. We then cast the plug in place.

We have painted the under deck areas, and the underside of the decks themselves, so we could glue and fasten the decks down.

Now that the decks are in place we are fitting the trim along the deck edge, and a bit more around the motor well. We are also working on rigging items to fill in the time gaps while we wait for something to cure.

After shaping the rudder blade and centerboard and adding the lead plug, we apply Dynel cloth saturated with epoxy to the leading edge and tip of each of these two parts. Then it’s time to fill and fair them before we are ready to apply paint.

Scott Whitlow from Shoreline Canvas was over last week and made a pattern for the canvas cover. The mast will be held in place fore and aft and will support the cover allowing water to shed off of it. You can see that the cover will come down to the bottom of the third strake. Originally we planned to have it come down one more strake, but with the flare of the hull being so great, it isn't necessary.

We are currently varnishing the gunwale. We're working on the top and outboard edges first; we'll varnish the inboard edges later. I think the photo has only two coats on, so it doesn't have the gloss it will in the end. We are also in the processing of varnishing the spars, tiller, oarlock pads and other interior bits and pieces.

We laid out the main on the floor of the living room and assembled the spars and confirmed that everything was a good fit before continuing with final shaping and varnishing.

These sails were made by Nathaniel Wilson Sailmaker of East Boothbay, Maine. He makes wonderful traditional sails. Here a few details of the workmanship

We've added a strip of fiberglass tape below the mast band to give it a wide shoulder to rest upon. Most of the spar will be varnished. The tip of the mast above the mastband will be painted the white of the hull color. We will coat the foot of the mast with epoxy mixed with aluminum for wear resistance.

Tom is installing a teak bracket forward of the motor well to reinforce where the motor is mounted.

We've fabricated and installed the coaming on both the fore and aft decks.

The rudder hardware is tricky to align on a curved sternpost. The hinge axis needs to be the same on both upper and lower hardware, and for maximum strength the hardware should be as far apart as possible, and for good looks it the rudder should be as close to the sternpost as possible.

Wherever possible we have the lower rudder strap capture the rudder blade axle. The threaded rod holds all the parts rigidly in line, while the threads allow for exact placement on the rudder and sternpost.

Then once the rudder is installed the tiller can be fitted. We steam bent the ash tiller to be just above the gunwale when hard over. The sweeping curve not only looks nice, it brings the end of the tiller to a more comfortable height. A tiller extension (also ash) is being bent to fit neatly on top of the tiller, several inches aft of the end of the tiller so as not to interfere with the helmsman's grip.

The first coat of primer is going on the exterior of the hull. It will take two (or three), and then it will mostly get sanded off in preparation for enamel. We were hoping to get enamel on the exterior over the weekend, but it looks like we’re going to run out of primer, and we won't have more on hand until Monday afternoon.

With the exterior painted (except for the sheerstrake), we now move to the interior. Sanding all of the interior surfaces is time consuming, but care and attention results in a superior finish.

We prefer a satin finish on the interior, usually a neutral beige or grey with an accent color or varnish on the trim pieces. This boat will have a light grey interior with grey–blue thwarts and benches and a white exterior with a dark blue sheerstrake. These two photos show the interior before the primer and enamel are applied.

Here Tom is using an HVLP spray set up to apply the undercoat to the interior. We apply two coats and then sand and putty any imperfections.

The undercoat sands easily and provides a smooth base for the marine enamel.

The thwart and the side benches are receiving their first coat of gray blue enamel. We are using Marshall's Cove Brand Marine Enamel paint.

Meanwhile, progress is occurring on the other painted parts. Here the rudder head is receiving its second coat of enamel. This is the same white as the hull.

We took advantage of a day when it wasn’t actually raining to let the parts air dry. The outdoors has significantly better air flow and the recent rains have kept the dust down. Keeping dust out of the paint and varnish is a challenge in a busy shop.

We have several parts in various stages of finishing. The rudder blade is clamped to the CY mold while it receives its final coat of enamel (the top of the blade is masked off because it is coated with graphite infused epoxy for wear resistance).

The 10 foot oars in the background are receving their fourth coat of varnish. We apply at least six coats of varnish to the clear finished parts. We’ve been having a small issue with suicidal bugs the last few days. What on earth attracts them to varnish? White paint is equally appealing, it seems.

Normally we disassemble the mold immediately after the boat is removed from the it to clear space in the shop. In this case we left the mold assembled, in case our next commission was for another CY, which it turned out to be.

We’ve spent the last few weeks watching paint dry. Oh, and enjoying the holidays with our families.

Finally the paint was hard enough for us to reassemble all of the interior parts – centerboard cap, thwart, side benches and floorboards. These four photos show the interior components.

This photo is looking aft. The soft gray interior looks great with the gray blue thwart and benches and the bare cedar floorboards, which will turn gray in trime. The water tight compartment to the left of the motor well will be useful to store gear you wish to keep dry.

Looking forward, we see the large storage compartment under the forward deck. Note the centerboard is graphite/epoxy coated for wear resistance and ease of maintenance. A garboard drain on each side of the centerboard will make it easy to wash out the interior periodically.

The floorboards remove individually without tools.

The mainsheet and block attach to the pad eye on the end of the centerboard cap.

Notice the turnbuttons used the hold the floorboards in place. We like this method because it not only holds the floorboards down, but also keeps them in place. A quick twist of the turnbutton, and the floorboard is easily removed without tools.

We mount a sacrificial teak pad on the forward edge of the motor well. It can easily be replaced in the future when required. When we cut the hole for the motor’s lower unit, we saved the cut out piece so it could be used as a plug when the motor is not in place. A stick attached to the plug is wedged under the teak pad to hold it in place. This also means you don’t have to stick your hand in icy water to remove the plug when you are ready to mount the motor.

Using the cut-out to create the plug results in nearless seamless surface on the exterior of the hull reducing drag.

Since the jib sheet passes throught the thwart knee to a cleat just aft of it, we installed a copper sleeve to reduce chafe on the knee. Carriage bolts fasten the benches to the thwart.

Rigging the gunter sloop requires some specialized hardware. Some we buy, some we cast ourselves in our small foundry. This photo shows the boom fitting and the jaws on the yard. We add protective leather where spars would otherwise get chafed.

We purchased the boom fitting as well as the mastband illustrated here. The diamond shaped copper pieces are covering the pins of the sheaves. This will allow for maintenance or replacement in the future if the need arises. The shoulder which the mastband rests on is reinforced with a few layers of fiberglass tape. This will prevent the mastband from crushing the shoulder when the rig is heavily loaded.

Naturally it was an absolutely flat calm day when we took the CY out for her first sail. We put up the mainsail, but accepted reality by puttering around using the Torqeedo 1003 Electric motor.

She moves easily through the water.

Even without any wind, the sail from Nathaniel Wilson, Sailmaker, sets nicely.

A few days later we tried again, but once more there was zero wind.

Finally, on Christmas Eve we found a few puffs and were able to enjoy a brief evening sail.

And of course, now that she is complete, we've turned her over to her proud new owner!

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