Author: gene.tehansky

A Boat Built on Commission

At the end of third quarter we soft launched the traditional grandy without sails while the sport grandy moved into the time consuming finishing process (sand, coat & repeat).  While waiting on the sails to be sewed and the paint to dry another boat project was in order. The commissioned boat ended up being a river dory or drift boat, often used to run white water rapids. These boats are characterized by their wide flat bottom, low draft and constant rocker shaped keel.  They were adapted from open water dorys used for fishing.  The design goes back to the mid 20th century where they were made of wood. Construction methods adapted to include aluminum, fiberglass and plastic.  One feature that sets a river dory apart from one used for open water is the addition of interior compartments, which provide storage and buoyancy.  

The newest boat project is 16 feet long, the frames are made from fir and the hull is marine grade plywood.  As with previous builds the boat will be constructed upside down on a strong back. The fir frames double as molds and are fashioned from the lofting. The frames along with the inner stem and transom are attached to the strong back in the appropriate orientation. Notches to accept the laminated chine log are carved into the frames, stem and transom prior to attachment.  The frames also get a set of limber holes that allow water to flow between frame bays. The chine log is laminated from 3 layers of 6mm plywood.

The next step is to fabricated the side planking which is made from scarfed 6mm plywood that is over 16 feet long.  The sheer was patterned and cut while the chine was left long and cut after attachment.   The bottom planking is 9mm plywood and was traced in place then cut on the bench.  Once fit, the bottom to side joint received piece of 5 in wide fiberglass tape.  They entire bottom was covered in 10 oz cloth and coated with epoxy where the last 2 coats included a graphite additive for abrasion resistance.

 

The outer stem is bonded and shaped in place. The sides received 3 coats of epoxy before primer and paint.  Extra care was taken at each step of the coating process to ensure the surface was completely flat with no texture. Next the boat is freed from the strong back and flipped over so we could begin working on the interior. Once the frames were cut to length the interior is prepped for epoxy coating.  If the results are acceptable it is likely the interior will remain bright.  

Boats built in the Norwegian tradition

During this quarter we had to the opportunity to travel to the shop of Jay Smith. A local legend who has spent a life time building boats in the Norwegian tradition. In his youth he apprenticed in Norway and the Faroe Islands. The current project is a 56 ft viking ship replica that will be used for tourism and education.

https://aspoyaboats.wixsite.com/aspoyaboats

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Thwarts (a place to sit)

The interior of both grandys are being fit out, in a small boat like this one of the main interior components are the thwarts. In this type of boat, the thwarts will be used as seats when rowing.  In the traditional boat the thwarts are supported by a longitudinal member called a thwart riser. The risers are a pair of oak stringers that run the length to the boat.  Conversely, in the contemporary boat, brackets are fabricated from fiberglass.  The front thwart in the traditional boat supports the mast, while the mast support in the contemporary boat will be higher.  Aft seating in the traditional boat is accomplished with sternsheets, supported by the thwart riser and transom mounted cleats.  The contemporary boat simply has another thwart in the aft section of the boat.  The thwarts for the contemporary boat are made from a sandwich of wood veneer, fiberglass, and foam while the traditional thwarts are solid western red cedar.   The contemporary thwarts will only require the fiberglass brackets for support, in comparison, the traditional boats have additional support from thwart knees.  The thwart shape for both boats is determined by patterning the top of the thwart using a spiling block of the appropriate thickness and measuring the bevel along the hull.   We expect this hull design to be tender, as such, it is likely that one will sit on the floor when sailing. The contemporary boat gets another sand along with a coat of primer.  After which the breasthook, quarter knees, and gunwales can be installed. The traditional boat receives a set of WRC floor boards.  One all of the components are dry fit they are removed and given a coat of oil varnish blend.  

Meanwhile the components for the sailing rig are fabricated. Both boats will have a rudder based on the Sid Skiff design, with a slightly different pitch along the transom.  The traditional rudder is made from solid Sapele with oak cheeks, while the contemporary is made from plywood.  The tiller for both boats will be made from solid white oak.  The rudder is attached to the transom using pintles and gudgeons, the traditional are bronze while the contemporary are made in the shop from fiberglass.  The centerboard can be installed, the centerboard for boat boats is a sold piece of G10 (a commonly used sheet good of high strength and density), cut to the appropriate shape.  

Prior to the writing we had the opportunity to do a soft launch of the traditional boat without any sailing gear.  We took turns rowing it around the harbor, and i believe she rows well (keep in mind I limited rowing experience).  She did develop a small leak in the bow between the garboard plank and the rabbet.  We repaired this with the same polyurethane adhesive we used to bed all the planking.  

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Finishing up Planking and Flipping the Trad Grandy

The planking for the traditional Grandy is complete.  In all there were 8 strakes totaling 16 planks.  All of the students in our group had the opportunity to hang a strake on the boat.  The process out lined previously was followed for all of the strakes with a few differences depending on how much shape the plank was asked to endure.  The planks were fastened together on the overlaps with copper rivets. However, the frame locations were skipped, the frames will also be attached via rivet.  In addition, cradles were made to hold the boat in an upright position.  This was done by patterning the hull at two stations and reusing some of the mold material to cut out the cradles.  The cradles allow us to flip the boat and start working on the interior

Once the boat is flipped a number of projects can be worked on simultaneously.  One of those is fitting the previously fabricated centerboard trunk. The trunk is held in place by 14 bolts through the keel and apron.  The centerboard trunk is installed prior to framing because the frames butt into the trunk at its base. Another project that being worked is carving the final transom shape.  This required consulting the old production boat and the plans. 

The next big project was framing, this boat has 32 frames made from white oak (3/4” x 1/2” in cross section).  The white oak was milled from timber that was green (dried as little as possible). Green wood more readily accepts shaping when steamed facilitating the bending process.  The boards were milled but framing wasn’t set to commence until the next week so they spent the weekend bundled up in the bay.  The idea is that they won’t continue to dry and may even absorb more moisture. Frames span from port to starboard sheer except at the centerboard trunk and a few frame bays in the bow.  In those locations the frame are shorter, terminating at the centerboard trunk or apron depending on location.  When it came time to steam bend the frames they were placed in the box for a minimum of 15 minutes.  Once removed they are gently pushed down into place.  The process of steaming softeners the lignin and allows the wood fibers to slide against one another.   One must work quickly to get the frames into place before they cool.  Once in place the frame is screwed to the apron (where appropriate) and then riveted through the laps of the planking.  It took us two days to frame the entire boat.  

Once the frames were installed we could turn to the process of finishing some of the components along the sheer.  For this boat this includes the breasthook which ties the stem and the planking together at the bow.  The quarter knees, which tie the transom to the planking at the stern.  And finally they inwale and gunwale, longitudinal members that give the sheer its structure along the length of the boat.  The breasthook and knees are patterned then fitted, and attached with screws.  The longitudinals are fitted for and aft with test pieces, then with some clever marking they are cut to the proper length.

Sporty boat

Both boats are close with regard to progress, with that we did one of our first objective comparisons.  The fully planked traditional boat hull, prior to frames weighed 110 lbs, while the glassed contemporary boat hull prior to fit out weighed 160 lbs.  I think we were expecting the traditional boat to be heavier, but in hindsight this isn’t a heavily build fishing boat. Prior to flipping the contemporary boat a veneer of Khaya was glued to the transom. This detail will be left bright providing a nice aesthetic. A keel was fabricated from fur for durability. Prior to installation, the centerboard slot was cut into the keel, along with a dado to accept the skeg. The slot was used as a template to cut a matching mortise in the apron. The keel was adhered to the boat with epoxy using screws as clamps.  Once the keel was installed the skeg could be fabricated.  The skeg is a piece of marine plywood cut to shape and fitted into the keel dado.  To help with durability a grove was cut in the lower edge of the skeg which was filled with epoxy thickened with additives for strength.  Finally, cradles are fabricated using an identical method to the traditional boat.  

Once flipped work commences similar to the traditional boat minus steam bending frames.  Transom is shaped, the breasthook, quarter knees, inwales and gunwales are fabricated.  Assembly is different from the traditional boat because all of these components are attached to the boat with no fasteners. In addition the interior of the boat is sanded fair and coated with epoxy (additional fiberglass is not required).

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Sailing Rig for the Grandy – Making a Birdsmouth Spar

As I have discussed previously we are building two boats from the same plans, one traditional and one contemporary.  The purpose of this endeavor is to compare the build techniques.  In addition, the traditional boat included a sailing rig borrowed from another small vessel (See Q2V2). Part way through last quarter we convinced our instructor that to have a proper comparison both vessels should have a sailing rig.  The design of the rig, centerboard and rudder will be the same between the two boats with some differences in the fabrication techniques .  For example, the composite boat will have hollow spars while the traditional boat will have solid.  The sail portion of the rig on our boats is a sprit.  A common sail configuration used on small sailing dinghies.  A sprit rig consists of two spars, a main mast and a diagonal yard called the sprit. 

The sprit yard for the contemporary boat will be made utilizing birdsmouth construction.  The center diameter is 2 inches which tapers to different diameters on the ends.  The process begins by sketching the cross sections at the known diameters.  The spar consists of 8 staves where the thickness is calculated based on the largest diameter of the spar (2 inches) and remains constant.  The width of each stave varies depending on the desired diameter.  A quick sketch is advisable to ensure the desired dimensions are possible.  The next step is to mill the staves based on the cross-section at the largest diameter, the species for this spar is sitka spruce which is lightweight and strong.  This milling includes the birdsmouth or v groove on one side of the width.   The taper required for the spar is shaped into the staves prior to assembly.  Two staves are used to mill down the remaining six by clamping them together on a work bench.

The staves are dry fit in cradles that hold them as close to level as possible. The cradles hold assembly while it is glued together with epoxy.  The next steps are very close to the practice spar I made back in week 8.  The only difference is that the initial shape is almost 8 sides to start with.  Once 8 sides is achieved you layout for 16 and then 32.  Every attempt is made to get as close to the finial shape with edge tools (hand plane and card scraper) before switching to a long piece of 80 grit sandpaper.  The ends are finished by turning 6 inch plugs out of fir, the ends could have been plugged with an octagonal cylinder prior to glue up as well.  Each end gets the necessary shape carved in them, one for the snotter connection at the mast and the other connects to the peak of the sail.  Final finishing will be 3 coats of epoxy then copious amounts of marine varnish.

Vacuum Bagging a Hull

Work continues on the sport grandy, in the last update we installing the first set of veneers attached with epoxy and held in place with plastic staples.  That surface was then faired and filled until is was as perfect as possible.  The third and final layer of wood is another set of veneers placed on the boat in a 90 degree orientation to the last layer.  Basically we are making a piece of plywood in the shape of a boat.   Once the pieces are dry fit the process is similar to most other epoxy applications.  Both the veneer and the hull are wet out with resin/hardener and a layer of thickened epoxy is applied to the hull.  Plastic staples are used to hold the panels in place but not as many as on the previous surface because this one will be clamped to the hull with a vacuum bag.

Vacuum bagging is a process where a vacuum is applied evenly across the entire part.  The “sandwich” that mades this possible includes, the wood veneers, peel ply (a release fabric that helps with resin distribution and prevents amine blush), breather cloth (fabric that helps with airflow and allow the resin to flow through the peal ply and not attache to the film), and finally the film (a plastic sheet that, along with butyl tape attached to the boat provides the seal).  A hose it attached to the bag with a “volcano” (plastic funnel looking fitting) and a vacuum is pulled where the target is 29 in/Hg. The vacuum is held overnight after which the sandwich can be removed.  This process is repeated for the other side of the boat.  The resulting surface is very close to perfect and required little fairing.

Once both sides of the boat have their final veneer layer the next step is finalizing the centerline which includes the outer stem and keel.  The outer stem is a lamination of 1/8” thick pieces of Sapele.  These laminations were first steamed with boiling water and attached to the boat to help change shape.  Once cooled, they were glued together, using the boat as a mold. The Stem is then attached and shaped round to accept a layer of fiberglass.

Prior to attaching the keel, the next piece of the boat’s centerline, we need to connect the sides of the boat together to make a cohesive hull.  First we adhered a tape of biaxial fiber glass to attach both sides together.  This is attached with epoxy and faired smooth.  Next the entire hill will get a coat or 8 oz glass to tie everything together.  Glass is laid from sheer to sheer dry and wet out with a roller.  The goal is a translucent surface where the fibers are still visible. The seem between sheets of glass is overlapped and cut with a roller.  Once the epoxy “tacks up” a fill coat is rolled on which is lightly thickened epoxy.  

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Fairing the Hull and Veneers

The strip planking on the sport (contemporary) grandy is complete.  It’s worth noting that the hull is extended 4 inches past the sheer (plywood was used to conserve cedar.)  This piece of real estate will be used seal the vacuum bag when the time comes.  Once the longitudinal cedar strips were installed the next step was fairing the hull.  Initially edge tools are used, your favorite #7 plane will do nicely, working diagonally to take away and high spots.  Then a long board, 3in x 12in (ish) board with 80 grit sandpaper is used to smooth out tooling marks.  One must be methodical in removing material, we don’t want to go all the way to the low points as this could potentially make the hull thinner than desired.  Once the appropriate level of fairness is achieved and the hull has been sanded as low as we dare, it’s time to fill the low spots.  The product used is epoxy thickened with a filler that will be easy to sand.  Once cured these high spots are sanded fair, this process is repeated a few times until the surface is acceptably fair.  

Once the cedar strip layer is fair on the outside (we’ll need to do the same on the inside!) the first veneer layer is next.  Our veneers are made from 1/16” Khaya, an African hardwood which has, in my opinion, an attractive grain similar to Sapele.  The veneers are installed at a 30 – 45 degree angle and are trimmed to fit the hull shape.  Working with a 1/16” material is nice as the trimming can be done with your favorite utility knife.  The first layer is fitted in sections then attached with thickened epoxy and plastic staples.  One must be cognizant of the staple length so they don’t poke through inside of the hull.  The boat really looks cool with its first veneer layer attached.

Traditional Lapstrake Planking

Planking on the traditional Grandy may seem like it is going much slower.  However once a cedar plank is installed it fairs itself and the hull is done (there are still frames that need to be added but we’ll save that for another newsletter).  The first plank that is installed next to the keel and apron is the garboard.  The garboard plank is important on a traditional boat as it helps to tie the frames and floors into the keel.  As such, it can be subject to a higher level of force when compared to other planks on the same boat.  The technique we used for capturing the shape of the garboard, and all other planks on this boat, is called spiling.  Spiling is the process of projecting a shape in two planes to a pattern, then projecting that shape back to planking material.  In our case that material is 3/8” western red cedar.  When spiling you transfer the marks on the mold from the lining out process.  Once the plank is cut, it typically has an unusual shape, and one must trust the spiling and not attempt to make any changes at the point.  The plank is offered up to the boat and the hood end is “rolled” into place while a partner holds the aft end of the plank up high.  If the fit looks close we can add gains.  Gains are the joinery at the plank ends that brings them to a flat surface.  

Once the gains are carved its time for the steam box, which is a box large enough to hold our plank and is full of a steady supply of steam.  General recommendation when steaming is the material is in the box 1 hour per inch of thickness. After 30 minutes the plank is pulled and clamped to the boat.  Once the plank cools the gains and overall fit is confirmed and the plank is fastened into place.  This process more or less is repeated for every subsequent plank.  Difference being the garboard is screwed into the apron along its length the subsequent planks are riveted the previous plank.  Riveting in the context to boat building is a multi person process.  A bronze nail is installed into the 2 planks with a rove on the inside.  The nail is then cut to length and peaned over the rove, creating a tight joint.

Susie Cat is Launched

Susie Cat is a traditionally built catboat that was commissioned by the private individuals for the school to build. The hull was completed by last year’s class and the job of finishing her fell to the school’s Prothero interns. She is 13’6″ catboat planked in western red cedar with steam bent oak frames. I was fortunate to be there for her launching and have the opportunity to go for a short sail in the Port Townsend Bay.

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Strip Planking the Sport Grandy

The hull of the contemporary boat is cold molded, consisting of multiple layers.  The first of which is cedar strips 1 1/8” tall x 3/8” thick.  The edges are left square sided, other options when strip planking include beveled or bead and cove edges which would be appropriate on a boat where the planking is visible (cedar strip canoe for example). For a cold molded hull the strip planking is not visible, as such, the additional space where the planks meet will be filled with glue. However, we still need to think about strip placement and how they will be tapered.  It is advantageous to taper long planks and minimize the number of short planks.  Planks should fall along at least 3 molds so they follow the fairness of the hull more readily.  The process starts out with a master plank that sits nicely amidship on the boat.  Then planking can proceed above and below.  This helps plan out where the tapers will be located.   The planks are held in place temporarily with finish nails at each station while the epoxy, applied to the edges is allowed to cure.  In between stations needs to be as level as possible, tape, screws and blocking are used. The more the planks are even the less that will need to be faired and filled later.  

Lining out Lapstrake Planking

For the traditional boat the backbone is fastened together with bronze bolts and screws.  Sica flex, a flexible marine adhesive and modern convenience is used in place of traditional bedding compound.  This helps with watertightness on a small boat such as this.  Some tune up of the rabbet is required at the joints of the various pieces of the backbone.

Before we can install the garboard (the first plank located next to keel) the sizing and location of all of the planks needs to be determined.  This process is called lining out and is literally determining the lines of the boat.  For this particular boat battens are cut at 3/4” representing the planking overlap, a typical attribute of a lapstrake style boat.  First a batten is placed along the sheer line and is adjusted for fairness.  There are 8 planks per side and we would like each of them (except for the garboard) to be equal width at each station.  First we establish the width of the garboard by taking the girth at each station and dividing by 8 planks.  We then add 1 inch so we know our garboard will be about 1” wider than the remaining planks at each station.  Now we can determine the width of the remaining 7 planks at each station.  We used a method called diminishing scale, where the girth measurements are held along a scale with 7 lines diminishing into the same point.  This allows us to quickly “tick strip” the girths and find widths with no measuring.  The battens are installed, this is the point where you can start to see the boat’s appearance.  It is also your opportunity to fix any thing that looks awry or unfair.  Batten locations are marked on the molds for future use.  

Marsh Cat gets paint and varnish

It’s been painted and looks pretty sharp in person.  When we started school the hull was complete but there was much to do to get paint applied.  The first step was to coat the brightwork (wood left as wood).  This meant three coats of epoxy and three coats of marine varnish.  Now we can paint the hull, which is done with a mono urethane paint and primer.   The primer coat brings out some of the remaining imperfections and is a perfect time correct them.  The mono urethane viscosity (when properly thinned) allows for high quality results using the rolling and tipping method.  My interpretation of the roll and tip method is that you roll with a roller and follow with a brush while still wet.  Using a high quality paint brush removes the roll texture and the paint lets the brush strokes disappear.  This paint cures hard, meaning it is appropriate for stiff substrate like a cold molded hull.  This finish would not be good for a live wood hull and repairing a small area can be problematic.  The deck of the boat also received a non skid coating consisting of small glass beads sprinkled on while the paint is wet and sealed in with another layer of paint.  This showed me that a paint job of this quality can be achieved with a little patience and A LOT of tape.

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When the process of lofting is nearing completion we can start work on our assembly jig.   The jig consists of, a strongback platform to hold the boat during assembly, mold stations that reflect the cross section of the boat and the backbone, the boat’s structural core.  Our strongback was made out man made timbers (wooden “i-beams” often used as floor joists).  These beams are built into a flat ladder structure with legs based on optimal working height. 

Concurrently station molds can be constructed.  Ours are a mixture of plywood and 1x12s.  For both boats we traced the station lines from the lofting onto mylar (along with the bevels).  The plywood versions are straightforward as you just use sail pins to transfer the lines and bevels (no need to worry about grain orientation).  The 1×12 method requires more attention to detail as you need to make sure you are using the long grain of the boards to your advantage, the shape of the boat may require them to be multiple pieces connected with gussets.  Everything is cut at the bandsaw, where the necessary rolling bevels are cut.  Cutting rolling bevels at the bandsaw requires a minimum of two people, one to drive and one to change the table angle to the appropriate bevel.  When cutting the large plywood pieces a third person was often needed for additional support.  I thought the plywood would be my preferred method but personally my results with the live wood had a higher level of accuracy as I could focus more on the cut.  Once the pieces are cut they are assembled on the lofting floor confirming and fine tuning the hull shape at each station and adding reference lines from the lofting to use later in the setup. Next the molds are attached to the strongback, making sure they are plumb and well supported. 

Crafting and assembling of the backbone pieces are next. We are building our boats upside down so the the apron fits into a recess in the top of the mold.  The transom is held in place by vertical supports.  Finally the stem is pinned at its forward most location and attached to the apron and/or keel (depending on the boat). The components on the composite boat are glued together, while the traditional parts are mechanically fastened (except for a small modern twist).  The composite boat stem is made from laminated sapelle while the apron and transom are made from Alaskan yellow cedar.  The back bone of the traditional boat is almost all white oak.

Carbon Boat Update

The infusion of the carbon boat was a success.  I love the look of carbon fiber and this has me thinking that a canoe made in this manner might be in the realm of possibility.  I made a time lapse video of the infusion and removing the boat from the mold.  Next steps are cleaning the boat and figuring out the design of the interior.  I think this boat will be the tender for the yacht, GloryBe, belonging to the school’s executive director.  For those that are curious the hull weight when removed was 42 pounds.

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A Grandy Update

Work on the traditional and contemporary Grandys continue. The lofting is mostly complete and construction of boats parts has begun.  To this point I am primarily working on the traditional boat.  That being said work on the contemporary is happening within my purview, the team is getting exposure to both construction methods.  Mold reductions, development of lines that define the mold stations, is where the methods start to diverge.  The contemporary has a thicker hull so the reductions are different.  In addition, the molds for the contemporary are being made from plywood, while the traditional will use live wood.  I don’t know the exact reason but I think it has to do with the fasteners required for construction.  The plywood molds are faster to build because grain direction is not a concern, however they may not hold a fastener as well.  We have also started allocating materials to build the backbones.  The traditional being white oak where the contemporary is lighter weight woods like cedar or other laminations.  

Another divergence, and activity that has been my focus is the sailing rig for the traditional boat.  The plans, developed by taking the lines from an existing boat, do not include provisions for sailing.  For this reason the rig will be based on an existing design from another skiff.  The sail plan comes from the “SID skiff” designed by, Ray Speck, a former instructor at the school.  The design gives us the sail shape, rig (sprit), rudder, centerboard, and a slick centerboard trunk design. The SID skiff is 13 foot long, six inches shorter than our Grandy.  This necessitates some investigation with regard to the location of the centerboard and mast.  We followed the direction of boat designer, John Gardner, through an article he wrote in Wooden Boat Magazine.  This article helps us determine the location of the center of effort (CE) and the center of lateral resistance (CLR).  The center of effort is located on the sail and represents the “power of the wind”.  The center of lateral resistance is one of the counteracting forces and is located under the waterline around the centerboard.  Without getting deep into sailboat dynamics, the CLR counteracts the CE and allows the sailboat to sail in directions other than downwind.  We placed our centerboard slightly forward of the center of the boat, per the article, which also allowed the thwarts (seats) to remain in the same place.  This is a rowboat and we don’t want to impact its “rowability” (moving the thwarts might do just that).  Once the centerboard is located we find the CR by balancing a model of the underwater profile on an awl (high tech stuff!). The CE location on the rig comes directly from the sail plan of the SID skiff.  For desirable boat dynamics it is recommended the CE “lead” CLR by a percentage of the length of the boat.  We chose our lead percentage based Gardner’s article.

Boats I haven’t shown before

Now that we are in the second quarter there are many boat projects going on at the same time. It’s a challenge to keep up to date on all of them. Here are a few that I haven’t shown before. I am not working on these boats directly so i don’t know all the details. However, if there are questions I will try to find answers.

Carbon Dinghy

It’s not a wooden boat the building process for this boat is interesting. The school scored a female mold of a small dinghy from a local boat builder. The process used to build this boat will be vacuum infusion. The parts are assembled dry into the mold and are sealed together. A vacuum is applied to the assembly which pulls the resin into the mold through carefully placed tubing. The assembly consists of two layers of carbon fiber with foam sandwiched in between. Once infused the assembly is “cooked” to cure the resin before being removed from the mold. The estimated weight for the hull of this boat is expected to very light. Stay tuned and I will report back on the hull weight.

A tiny ship designed by Peter Culler

It’s not actually called it a tiny ship by the designer. That’s a name some of the students gave it as it came to fruition last quarter. Yes this was actually one of group’s first quarter skiffs. As you can see its much more involved than the flat bottomed Sprite my group started building. I can’t speak to all the details of the construction by I can say it has a pretty substantial backbone and some amazing bottom planking. As you move forward on the boat the amount of twist required a lot of shaping by the boat builders. The irony of Culler’s comment from his book, “Keep Them Simple” is not lost on me.

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Tale of two Grandys

The Grandy Boat Company, founded by Lewis Lee Grandy, operated around the Puget Sound in multiple locations from 1903 to 1967.  During that time the company built boats of many sizes and purposes.  One variety included lapstrake dinghies, one of which can be found hanging in the mill room of the Westrem shop.  The school has built versions of this boat at different lengths and construction techniques from plank on frame to cold molded carbon fiber.  At one point, I am not sure of the history, Iines of a 13’6” Grandy were developed from an existing hull and turned into a set of plans.  We are going to build our vessels from these plans, perhaps for the first time.  To make the build even more interesting two vessels will be built side by side, an activity I alluded to before winter break.  One will be using traditional plank on frame techniques and the other will be cold molded.  The hull of the cold molded boat will be made of multiple layers.  The first layer will be cedar strips oriented lengthwise (similar a cedar strip canoe).  The next layers will be live wood veneers oriented such that the wood’s grain direction in all 3 layers is different.  Once a layer of fiberglass cloth is added the strength of the hull will require no frames.  The traditional boat planking will be lapstrake western red cedar with steam bent frames (probably made of white oak).

The intent of this exercise is to do a side by side comparison of the two construction techniques, comparing cost, speed of build, material waste and most importantly (some might say) which is faster in the water.  We started by lofting the both boats.  The lines of the plans we are using are designed to outside of planking which means they will be identical.   The two boats will diverge once we get into the mold reductions.   As we discussed in the newsletter on lofting (week 8) the mold reductions take into account the planking (or hull) thickness.  The traditional boat’s hull thickness is 3/8” while the cold molded boat is 1/2”. As a result the molds will be slightly different.

Field Trip A Mast for TallyHo

TallyHo is an English sailing yacht, designed by Albert Strange, in 1909.  She is a historic Gaff Cutter that is undergoing an extensive restoration, documented on YouTube (@SampsonBoatCo).  The videos have an entertainment focus which I think contributes to their popularity.  The channel, SampsonBoatCo, as of this writing has 432K subscribers.  

The restoration work is being done in the Port Townsend area and we recently had the opportunity to see part of the construction process of the main mast at the Northwest Maritime Center.  The workspace at the maritime center is amazing and is rented out to the community for all different types of personal and commercial projects.  In modern times a shared space such as this is a rarity.  The main mast is hollow and is being constructed with a box barrel stave technique.   This method was chosen based on the quality of the spruce, limited waste and input of the naval architect that designed the spars. The mast is glued together one side at a time, after which blocking will be added at the base where the mast meets the boat and for various hardware. The hollow mast also facilitates wired connections for modern conveniences that are mounted aloft. The main mast is one of many spars that will be on TallyHo, approximately 190 lineal feet of spars in total.

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Planking the skiff

Spoiler alert, our skiff had all her planks installed just before the end of the first quarter. I was pleased to be able to reach this milestone before winter break.  We divided the workload into a few teams, I was on a team working on side planking.  In the last newsletter we had installed the garboard strake on both sides.  For the 2nd strakes (not sure if this one has a proper name) we started off by creating a pattern on the plank by simply holding it up the boat and marking reference lines.  The challenge is the material is at full size does not want to conform to the shape of the boat (especially at the bow).  As a result we methodically remove material until we are satisfied with the fit,  I believe it took 5 or 6 fittings, where each time, we gained a little more information and moved closer to the final shape. The gains and ship lap are carved into the bow and the stern (see pictures), then the plank is riveted to the garboard, avoiding frame locations.  The process for the 3rd strakes is largely the same except we used a patterning technique where we attach a piece of patterning stock narrower than the strake and hot glue small tabs at each reference mark.  This shape is then be transferred to the stock.  We did less fittings this time, the number of fittings required depends on how confident you are with your patterning.  During one of these fittings I was clamping the strake to the stem and it happened, I cracked the plank (a big one right down the center).  We tried rescuing it with some glue but alas it cracked again.  So we made a new plank and learned about steam bending.  I didn’t take a picture of our setup but if you can imagine a propane fired turkey fryer burner heating up a 30 (ish) gallon tank of water to a boil where the outlet goes into a long box.  The box is sized such that is can accept long planks.  Steaming the plank breaks down the lignin (the natural glue that holds all the wood fibers together) and allows it to become flexible.  When warm, if the plank is clamped to a specific shape when it cools it will take on that shape (results may vary).  The general rule of thumb is 1 hour per inch so we left our planks in the box for 30-45 mins.  When steam bending planks organization is key, having everything in place when the plank comes out of the box.  For our situation we clamped our plank to the boat and let it cool.  You can see some pictures of the sheer strake after steam bending.  For the sheer strake we patterned using the drawing arcs method, where a set of dividers is used to make reference points using multiple arcs.  When you lay the pattern out on the stock those arcs are used to transfer points.  We steamed the sheer strake as well and spent a little more time comparing each side as this is the of the boat and we wanted it to be as symmetrical as possible.

While all this steam bending and riveting was going on another team was hard at work planking the bottom.  The planking on the bottom is also cedar but it was milled from 4x4s from a local hardware store.  Its amazing the local hardware store is carrying stock this nice.  The bottom planking is carvel so it is milled with a bevel to accept cotton caulking (sounds like corking on the west coast) between each plank.  The caulking not only helps to seal the planks from water but also an integral part of the structural integrity.  The team started at the stern of the boat, laying out 3 to 5 planks at a time.  Taking care to make sure they are square to the centerline of the boat and are compressed tightly together.  Once fitted they are removed and a layer of flexible adhesive along with a cotton string are added.  The string prevents the adhesive from being squeezed out of the joint and lets it act more like a gasket between the bottom plank, chine logs and apron.

A common tradition in boat building is the whiskey plank.  The builders (and whomever they invite) have a small toast and celebration when the last plank is installed.  I imagine this milestone in the boat build process could be used as a motivational tool back in the day.  Its pretty straightforward, you drink some whiskey and splash a little on the boat.    We had our whiskey plank celebration on the last day of the quarter. We also had the genius idea to flip the boat over and see what she looked like, even though there is still plenty of stuff to do while she is upside down.  I am pretty happy with how my first boat project turned out, we named her PRETTY ALRIGHT.

First quarter wrap up

So that’s a wrap for the first quarter.  When school starts back up in the new year I’ll be in another shop so I won’t be working to finish out this boat.  The projects I have asked to work on are the Marsh Cat and traditional Grandy.  The Marsh Cat needs interior woodwork, rigging and finishing.  The traditional Grandy is a ground up build that will be built next to a cold molded Grandy from the same lofting.  An experiment to compare traditional and contemporary building techniques.  There are many boats in my new shop, I anticipate contributing to some other boats as well.  Looking forward to it!

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