Polysail Dave Builds a (Second) Sharpie
by Dave Gray
(Dave Gray is the proprietor of HR-Solutions/Polysails)

I’d been out of the boatbuilding business for a while—at least since Christmas—and my wife was beginning to daydream aloud about being able to park two vehicles in the garage this year. But I had been secretly designing boats ever since I finished my new grandson’s Christmas present, a miniature rock and roll 5’ skiff of my own design. The Jackson Doyle was probably the only boatbuilding project that ever had my wife’s wholehearted approval since I acquired this vice. My grandson’s boat now serves as a giant toy box in the family room at my daughter’s house. A future sailor needs a giant toy box for his giant toys, apparently.

For a while, I toyed with the idea of building a catamaran. I thought that our 24 year-old son and his wife would probably like a boat like that. They’re a Navy couple, and they like to go fast and spend time in the sun. Of course, his idea of fast is sailing along in the space shuttle while my idea of fast is sailing along in a home built dinghy in a modest wind.

Our son had recently completed his last submarine patrol and had tried to trailer the OK Dinghy I had restored for him from his post at Kings Bay, GA to his new location at Saratoga Springs, NY. But the salt air had taken its toll on both the trailer and the boat, and when the trailer tongue broke and carved a trail in the highway just outside the Kings Bay base, he made the wise decision to make a gift of the whole package to the tow truck driver who was called to the scene of the disaster. I believe he received counsel on this decision from a representative of the local sheriff’s office.

A month into the catamaran research and design, I decided to build a half-size model of one of the hulls. Once I started spending a little too much time in the garage, the cat was out of the bag. Initially, I tried to persuade my wife that the PolySail business was booming. However, that story came under immediate suspicion due to some mysterious feminine profiling ability combined with the bank examiner's financial instinct she seems to possess. Instead of buying my tale, she suggested that I had taken up smoking again after a 25-year lapse. Confronted with that accusation, I needed a quick explanation for the secrecy. Let's see, I was now working undercover for the CIA—no, that would never fly. She could check that story out with her uncle, a CIA retiree who knew everything about me before he even met me for the first time. Then it came to me! I was actually building her a surprise birthday gift in the garage—the wall of shelves she had wanted for her scrapbooking supplies!. It was the perfect evasion?-a stroke of genius?-except that, damn, the project took weeks to complete. What a setback! But the shelves were beautiful, and my birthday gift was a resounding success.

Being in good graces with my wife of 30 years is a rare event, so I decided to take advantage of the moment, take her out to dinner, and privately discuss the dire need to build a boat—not for myself, of course, but for our son who had so tragically lost his dinghy. I even admitted to having a half-size model of a catamaran hull stashed above the garage. Seeing that there was going to be no stopping me, Dixie tried a final diversion, suggesting that I get our son’s input on the catamaran I was so eager to build. The strategy made too much sense to avoid, so I made the call. Try as I might, I couldn’t detect much enthusiasm in my son’s voice for another boat. No doubt he was still mourning his earlier loss.

Her diversion worked, but only for a short time. I abandoned the catamaran R & D project, and reassessed my options. Eventually these ramblings recalled the piece I’d written for Chuck Leinweber’s Duckworks Magazine in late January. In Decision Time I concluded that, besides helping others learn to enjoy messing about in boats, I might have to design and build a catamaran or a flattie skiff to add to the PolySail repertoire. Ahah! What a revelation! I was truly back on track. Sharpies forever! Back to the drawing board.

First I reread Reuel B. Parker’s The Sharpie Book and parts of Howard Chapelle’s American Small Sailing Craft. Next I picked back through my library of Phil Bolger books looking for his smaller sharpie designs. Then I took a long hard look at some plans that had been sent to me a few years ago by Christopher Ring of Austin, TX. The plans are for a nifty little15’ cat-rigged sharpie that a New England builder once built in small quantities. I almost decided to build that boat. But then I picked up Jim Michalak’s new book Boatbuilding for Beginners and Beyond and was reminded again of my decision to keep things simple. After all, simplicity is the essence of sharpie design and building. Here are the six basic steps.

• Fasten a couple of identical sides with the chine logs and wales already attached to a (nearly plumb) triangular stem.
• Spring the sides around a central form, and fasten them to a trapezoidal transom.
• Add a keelson (a bow to stern plank along the inside of the bottom)
• Then, either plank across the bottom or cut a plywood shape to fit the bottom outline.
• Add some seating, bracing where needed, and a means of propulsion.
• Seal everything with epoxy, glue, sealant, and/or paint.

Voila! You have a small version of a very uniquely American workboat/racing design nearly ready for the water.

I’d built a 16’ sharpie a few years back and learned a few things from that experience. I tried to rush Foolhardy into existence in order to have her ready for the annual Lake Monroe Messabout, and I took too many shortcuts, both in design and execution. As a result, she had a leak I could never find, and her finish deteriorated quickly. However, the few times I had her on the water, she lived up to the Sharpie’s reputation for speed and stability. She now sits down by the bank of our little lake awaiting major repairs or break up depending on what I find when I turn her over after completing this project.

With Foolhardy, I did little more than sketch out some drawings and cut out a cardboard scale model before I started slapping together the boat. That ease of construction could be considered both a weakness and the strength of sharpie design. It’s thought that the sharpie had its origins in New England, where it’s stability, load capacity, and speed proved valuable for harvesting oysters on the shallow, rough bays. Oystermen could easily copy rough designs from other builders and construct their own boats in very little time. No plans were really necessary. Like the oystermen of old, I didn’t really keep a record of Foolhardy’s lines and offsets. I promised myself I would keep measurements this time because I hoped to end up with a boat others might want to replicate. (But as it turned out, I didn't)

One of the lessons learned from Foolhardy was that slight alterations in the central form, stem angle, and transom change the appearance of a sharpie dramatically. For this boat I hoped to keep the design simple and easy to copy. I had visions of providing novice builders with a boat kit consisting of the stem, central form, transom, and instructions that could be easily shipped. The builders could provide the plywood and wood needed for the sides and other pieces. To make the design even more foolproof, I hoped that the novice builders would need to make only three cuts in creating their sides. With the right combination of stem, transom, and central form, I reasoned, the sheer could start as the straight line formed by one edge of two pieces of 4’ x 8’ plywood butted together.

By altering the angle between the bottom and the side made by the central form, the sheer would have a nice fair curve when bent to shape.

To try to get the right combination of these elements, I decided to build a simple hull model from 1/8” lauan at a 1:4 scale. Building the model would at least preserve some of the more important measurements as this project took shape. When I didn’t like the hull shape on the first model, I built a second one that was much more to my liking. The first model joined the catamaran hull in the garage attic. Below is the second hull model.

Note how the central form has shaped the originally straight edge into a nice fair curve. Note also that the chine of a sharpie has a slight S curve between the center and bow. This slight S curve is apparent on the side view of the model but not on the diagram.

The hull model later became a full-fledged sailing model. I’ve since experimented with the model on our small lake to help get a feel for the way the full-sized version will sail. The model was also put to use in a couple of school classrooms at a rural elementary school shortly before the end of school. In the picture at left, “Captain Drew,” a first grader I tutored in reading, places sailing vocabulary words on the model to show off his newfound knowledge to his classmates. Later, the class took the model out to the school pond to see if we could sail it across the pond. We had to place a fairly large rock in the bottom before we could make it across the pond without capsizing when the wind gusted. If the boat capsized, it was Captain Drew’s responsibility to drag the model back to shore using the attached line. It might have been the first time all year that Drew was the envy of his first grade classmates.

One thing that became clear from the tests with the model was that the full-sized boat would require significant flotation if I wanted to be able to right the boat single-handedly after a capsize. (I'm still concerned about that revelation.)

In reality, some of the model building occurred at the same time the full-scale hull was being built. The side view of the model hull above provides an edge view of some of the 4’ x 8’ sheets of plywood I had obtained. One of the local specialty lumber companies had advertised a special price on their ¼” “marine” plywood in February, so I had purchased about six sheets in anticipation of a future project. (I’m still a little suspicious of this “marine” plywood. It looks like plain old AC grade to me). I also had several 8’ lengths of mahogany and white oak boards in stock that I had purchased last year. Some of the oak had found its way into the Jackson Doyle as boat parts and rockers, leaving me with more mahogany than oak, so I figured I would use the mahogany for framing up the sharpie.

The fact that I already had invested in the ¼” plywood predetermined the thickness of the sharpie’s skin. Since I mostly sail on smaller lakes and protected waters, I wanted a lightweight boat that I could muscle around by myself both in the building process and in trailering the boat to other locations later. My experience with Foolhardy suggested that a finished sixteen-footer with even a thin skin was a little more weight than I could now handle, so this hull was intended to have a modest 14’ 6” length overall (Loa), a relatively narrow 3’ 7” waterline beam (Bwl), and a short 10’ waterline length (Lwl). I found John Teale’s How to Design a Boat a useful reference in determining many of the designed dimensions.

I had used 4' x 8' panels butted together, glued with epoxy, and covered with fiberglass strips on both sides to form long side and bottom panels on three previous boats with no signs of failure, so I decided to use the same approach with this sharpie. The trick is to sand out a slight hollow where the boards butt together so that the joint will appear flat after you epoxy the fiberglass tape over the joint on both sides. Of course, this approach isn't a cure-all. You still have to fill and sand, fill and sand, fill and sand...to get any joint to disappear. The joint will have a better chance, though, if you have an absolutely flat surface to work on and plenty of weight on the joint to keep it flat throughout the process.

After creating two 4' x 16' panels, one for the sides and one for the bottom, I marked out the sides on one of the panels to my station marks and cut out each side. The masking tape helps prevent splintering along the cut. In most cases I used clear packing tape for this purpose because the marks and lines will show through the tape. However, I used the blue masking tape in these pictures so that the lines would readily show. The portable saw in the picture made cutting along the long chine lines a simple task. I highly recommend buying one if you plan to build shelves or boats and happen to have a couple of hundred dollars that might be otherwise employed in less worthy endeavors like grocery shopping and such.

Once the sides, stem, transom and central frame were cut out and assembled, the hull began to take shape. I used a chalk line down the middle of the leftover 16' plywood as a centerline and matched the center of the stem, middle frame and transom to that line as the pieces were assembled. To use this method requires a good eye and pieces that are symetrical within about 1/16". For those kinds of tolerances, one really needs that $200 portable saw.

Attaching the chines and gunwales to the sides before assembling the sides is a recommended procedure. Usually this method leads to fairer lines than are possible with the method I used.

Note the small arc on the bottom of the center form. I reasoned that I might get away with a tortured plywood bottom if I kept the arc small and flattened the run to the transom. (I wanted a flat area aft for possible planing.) I don't think that I would try that experiment again. That decision complicated numerous measurements and caused trouble in attaching the bottom later. Knowing that many of those results could be expected, I chose to experiment with this reputedly faster bottom anyhow?even after promising myself that I would keep things simple. After all, one never knows when he is building his last boat.

After attaching the outside chine logs, completing much of the interior framing, and adding the cedar keelson, I attacked the attachment of the bottom. Lots of stainless steel screws and epoxy helped draw the bottom up snugly. At least there were no gaps large enough for a lurking hippo to crawl through. I had used up some leftover fiberglass on the inside of the bottom, thinking that I would only need to cover those areas that got heavy use. In retrospect, I wish that I had covered all the interior of the bottom for better protection, appearance and strength. I also wish that I had placed a couple of temporary thwarts across the hull at this point to protect the lines of the sheer. Adding fairly heavy wales later in the process tended to move the widest point in the boat aft of the central frame.

At this point I was faced with a difficult design decision--centerboard, dagger board, leeboard or... something else. I considered all kinds of crazy options, including double-hinged boards, scissor affairs, and the folding brass centerboards advertised in Messing About in Boats. In the end I decided that I would have to try out a leeboard. In part, this decision was determined by the expected location of the mast and the center of effort of the initial sail plan. In order to place a centerboard far enough aft for slight weather helm, I would have to split the central form with the centerboard trunk. Visions of Old Faithful springing from that unstable juncture washed away the centerboard option, and left me with the happy prospect of enough room forward that I would always have the option of adding a small cuddy cabin.

Cutting and attaching the leeboard supports almost proved to be my undoing. I worried those measurements and cardboard templates to a new level of exhaustion before cutting the mahogany supports. Even then, I blew a compound angled, curved cut that would have had the leeboard on the starboard side rather than the leeboard side where it finally found a home. The finished leeboard is 4' long and includes a 10 lb. weight near the bottom forward edge to keep it down. Jim Michalak's new book was very helpful in suggesting how to mount the leeboard. I'm not certain that I followed all his instructions, but I like the finished look. Viewed from the front with her leeboard stored, the sharpie appears to have a jet intake on the port side.

The big leeboard and Scimitar sword-inspired rudder assist with tight tacks?not a characteristic of most sharpies. Since the original sharpies were conceived as simple workboats, they had long, shallow centerboards and rudders that allowed the boat to float with the rudder virtually untended in a straight course across the oyster beds. One of the original 30-35' sharpies would nearly create a bridge across the shallow channel where I live, so I need good tacking ability and kick-up boards to get around and out to the main body of my little lake in Indiana.

Now I understand where the term rudder "cheeks" originated.

Since I've now had the opportunity to test the boat, I can say that I'm pleased with her agility. In the picture below, I am checking the hull for leaks and trying to determine the actual vs. the designed waterline. I'm sitting on a cooler just aft of the central frame which will later support a seat. Only about 9' of the 14' 6" hull appears to be touching the water. With her rudder on, I think I'm going to like this design. But I'm definitely going to have to find some longer oars if I'm going to row her.

This boat was built, in part, as a testbed for my PolySail Kits. The mast step slides along the keelson and is secured by a single screw. Mast partner thwarts can be screwed to the inside gunwale at nearly any location. The leeboard and rudder angles and depths are adjustable. Floatation can be added or removed. The center seat and the aft "jump seats" are easily removable to allow the skipper to relocate his 190 lbs to the bottom for sailing in heavier air. But in lighter air or when rowing, it's nice to be able to sit on a seat and cushion and enjoy some conversation with the crew. Over time, I hope to test a variety of PolySail designs, mast locations, and rigging options with this little boat's flexible design.

Up to the point of putting her hull in the water, I hadn't thought much about a name for the design or the boat. Once I had completed and painted her 18' mast, though, naming the boat started climbing my priority list. My nephew Andy forced the issue one weekend when he said he would cut out the boat's new name in stainless steel when I trucked Hot Tub III up to him to replace the aging and waterlogged Styrofoam version Hot Tub II. Forced to make a decision, I settled on Essence, hoping the boat would have the substance and heart to match the name.

I hoped to get Essence finished and and officially launched at an amateur messabout in Kingston, Ontario, that I wanted badly to attend. Unfortunately, circumstances arose that prevented me from preparing my trailer and the boat for the long trek. Now my sights are set on an official launching at the nearby Lake Monroe Messabout held each September near Bloomington, Indiana. Of course, I've quietly been testing here at Lake Vista since early August. The unofficial sailing date was Sunday, August 10th, 2003. The following Saturday morning was photo day with my daughter snapping away from the hillside at the Gray residence. Below is a photo from that day.

I wasn't happy with the 20 lb. wood mast I made for Essence. My Hollowood spar weighs just ounces, and I wanted something similar for the mast. However, getting lightness and strength usually means spending big bucks for a carbon fiber or production aluminum mast. Nephew Andy has been turned loose with some money and an idea for a lightweight steel mast that appears fairly stiff and strong up to about 17', but I don't have a progress report yet. The prototype is 18' by 1" 5/8" x 1 1/4" and weighs just 7 lbs. At least 2 of those 7lbs. are probably in its vinyl tape wrapping which I hope to eliminate in favor of paint. Even with its tape wrapping, this lightweight steel mast floated on the surface of Lake Vista.

I might have to patent a kit form of this mast if Andy's modifications can be made inexpensively.

Using this mast will require some adjustments to the partner and the mast step of Essence. The current wood mast is plenty beefy at the base and at the partner, so a new partner is in order. I might be able to get by with the current step if I cut some wedges to fit the much smaller base of the steel mast. I've tried the steel mast out in light airs once with an "Ohio" version of my jib-headed, sprit boomed PolySail. Although this "Ohio" spreet sail has only about 80% of the area of the sail in the photos, it seemed to perform even better.

The sail in the photographs of Essence is a five-year old PolySail that I originally made for Foolhardy. Taking it off its original mast, I found the sail to be in good shape considering that the edges had only been taped with double-faced tape. Except for an 18" strip along the leech, the adhesive was still holding. I was able to run a stitch around the edge, make some adjustments to the leech so it wouldn't hook quite so much, then take the sail out and use it. However, I think that at nearly 80 sq. ft., the sail might be a little large for all but the most tranquil sailing conditions. With the shallow draft on Essence, she behaves more like a 9-10 foot pram than a 14 footer. I'd feel a little more comfortable with this sail if I had crew along to lengthen the waterline and counterbalance the force of the wind.

I like the idea of having a craft that can be fine-tuned for many different sail configurations. For me, finding the optimal combination of board adjustment, weight distribution, sail "set," etc. is what makes sailing so intriguing. I'm looking forward now to the "official" launching of Essence at Lake Monroe and to experimenting with her for years to come.

Dave Gray is the proprietor of HR-Solutions/Polysails