Saturday, January 16, 2010

Sail Design and Building, Version I

In no time, I had the basic hull done and ready to flip over onto its trailer, where it would ride until launch day. A crew of friends came down to help me with the roll-over, and It seemed like the end was almost in sight. Then things slowed way, way down.

Maybe a lot of first-time boat builders discover that the sail rig of a boat takes a long time to put together. It was worse, because I was designing mine from scratch and sewing the sails. Moreover, I wanted an adjustable system of steps and partners, three of each as I will explain. And as I was to learn, when you modify any small element of boat's design, it can have ramifications from end to end. It gave me a deep appreciation for Phil Bolger's work to be an amateur at it.

So, if I think so highly of Phil's art, why mess with it? As I mentioned before, experimentation was my goal before I even chose a design. But I have to admit I was not fond of either of Birdwatcher's designed rigs on paper. Phil Bolger told me of a fellow not far from me who had built a Birdwatcher, Aeneas Precht. His boat is gorgeous, radically customized and built of Airex. (If anyone has a link to the pictures of it that used to be online, please send.) Anyway, Aeneas told me the Bolger solent rig was very unwieldy to handle, did not set as well as he liked. As for the smaller leg o'mutton rig, it was by all accounts too little canvas for the light airs you experience lake sailing. 

Historically, most sharpies had two sprit sails in a cat-ketch configuration. "Reefing" was done by taking down one of the masts and moving the remaining one to a middle position. It seemed like a good starting point. And for me it was a way of exploring a bit of history.

I set about drawing the rig and went through many iterations. I looked at the sharpies in Reuel Parker's Sharpie Book, looked at the many boats in the books of Howard Chapelle, of Francis Herreshoff. I eventually settled on four-sided sprit sails with sprit booms. Bolger describes many advantages to this rig in his hard-to-find 103 Small Boat Rigs — short spars, low stress, good windward ability for a low-tech rig. To balance the sails properly, I simply positioned their combined centre of effort in the same position Phil Bolger had placed his centre of effort. If my centre of effort was off, I had the movable mast steps to provide some adjustment leeway.

The sail rig you see in the title photo of this blog, and the picture above, is pretty close to that first design. 

For the masts I used grown trees about four inches in diameter at the base, fire-killed spruce from a burn up north. The trees were die-straight, branchless and barkless yet still standing three years after the fire. They say air drying makes for strong lumber. These were strong enough to stand on without breaking. To prepare them, I just pared them a little with a draw knife, then oiled them. Their natural irregularities are all but invisible, and the time saving over built up masts was enormous. As for hollow masts, there is not much weight savings on spars at this small size. I also used trees for the peak sprits, though these are a bit too heavy and I will make some lighter spars when I can. I love the low-technology. When I sail in remote areas, I bring an axe, saw, draw knife and hand drill, comfortable in the knowledge that I could replace an entire mast in not much time just by going into the bush and taking a tree.

I mentioned adjustable mast-steps and partners, and having three sets of each to accommodate having either one or both sails in play. For the partners, I just made mine out of wood. To make their position adjustable, I have them sliding on a kind of wooden rail attached to the coaming. The mast step also slides on a rail. The partners are wide open on one side, and the masts are held in place by 2-inch cargo straps. The straps attach to a cheap, galvanized kind of cargo tie-down track.

All this is easier to see in a picture, looking down:

And here is a shot with the rig stowed, where you can see the mast partners more clearly:

The cargo strap and track idea was intended to be temporary, to aid in the experimentation phase. But it is immensely strong, dirt cheap and very easy to use. The wide straps and partners do no damage to the mast. The track serves as a kind of toe rail, and it is very handy to be able to attach a ring at any position along its length — for jib sheet blocks, dock lines, etc. I can't imagine doing without it now.

The sails themselves I ordered ready-to-sew from a good American company called Sailrite. They deliver computer-cut panels that only need to be stitched up. I had some slight experience sewing heavy fabrics, so decided to tackle this job. Many people just hire a sail loft to build them sails, having no taste for sewing. (If that describes you, then you can either skip to the next post, or just read on and find out how the other half lives.) 

Sail-shaping is an art; mere sail-sewing is not too difficult, but information on doing it is hard to find. The testimonials I read on the otherwise excellent Sailrite website all seemed to be from people who had sewn a lot before, and they didn't address the realities of struggling with a home sewing machine. I want to stick to Birdwatchwer-specific information on this blog, but I will digress into some how-to in this case.

From a skills standpoint, the techniques you use on a sail are very straightforward, much more rudimentary than making clothes. Even if you have never touched a sewing machine before, you will manage fine if you get someone to show you the basics of a simple stitch, and then practice some runs on scrap pieces. 

The ideal sailmaking equipment is a walking-foot, commercial sewing machine surrounded by 200 square feet of table or more, and maybe an apprentice you can order about. But you can manage with humbler arrangements. We had an old Singer, but it didn't do zig zag, which you need. So I took some of my scrap sail cloth and went to a repair guy who also sold machines. I told him my purpose and asked him to find me the sturdiest home machine possible. He said almost any heavy older machine with a sharp needle will pierce many layers of heavy material. The trick is finding one that will keep tension on the thread. He sold me a 1960s Kenmore that weighs as much as a small anvil. He wanted $40 for it, but — since it came with good advice about dealing with heavy fabric, a demo using my scrap, and a story about his sister that was both funny and sad — I made him take $60. My guru showed me how to wind the thread around the thread tensioner twice, and really tighten down the bobbin screw. You will certainly have to feed the slippery polyester sail cloth by hand because the feed dogs of a typical machine cannot get a grip — but that isn't hard after a small bit of practice. 

A portable machine can be set on any flat surface, and working on the floor would seem sensible. But then you are in the wrong position to use the little go-pedal, and it just kills the lower back. To work sitting up, you will need to jury-rig a collection of tables to hold your sail as it grows. An arrangement similar to the infeed and outfeed tables you see around table saws is what you want. Once you are set up to work, you can complete the machine sewing on a fairly large sail in a day. There is usually some handwork to finish the sail, and you often need spur grommets in the corners. Setting spur grommets requires a special tool. I just take my finished sails to a tarpaulin place and have them set grommets for me. I have now made, repaired or altered quite a number of sails, each time wishing I had the right equipment and work space. Somehow, the pleasures outweigh the troubles for me, but only just. 

Wednesday, January 13, 2010

Tinkering with the best-laid plans

My intent to experiment with the Birdwatcher design had to do mostly with the sail rig, which I will deal with in its own post. As for the boat itself, I did not plan to deviate from the drawings, and didn't much. The Birdwatcher is a great boat as is. But once you get into the dust and screws of a project, you start to think about how things could be tweaked differently. Here and there, I found a few ways to construct the Birdwatcher more simply, and more strongly.

As I mentioned last time, the basic hull comes together very quickly. You position the frames on a strongback, plumb and square them up, scarf together the side panels and hang them on the frames and screw them into the stem and stern pieces, and before you know it you've got something boatish.

You can build Birdwatcher with the chine logs inside, outside, or none at all, relying on epoxy alone. I chose outside logs because it seemed a good idea to have some lumber where the boat was likely to take a hit. When a sharpie heels over to sail, the chine becomes a keel. I read somewhere that exterior chine logs also gave you a toehold to climb back aboard if you go for a swim, planned or otherwise. In practice they do, though it takes a lot of upper body strength to climb up even in ideal conditions. Re-boarding would be nearly impossible without the external logs.

I had already decided to at least give leeboards a try, so I did not build a centreboard right away. I determined, however, that if and when I did put in a centreboard, it would go on the port side, not to starboard as Phil Bolger showed it on his drawing. I never got a chance to ask Phil his rationale. Mine was this: the mast is stepped on the same side as the centreboard. You hoist it onto your shoulder and walk it upright. I figured it would be better for a right-handed person to have the mast on the left shoulder, so when you get it into position, you have your good mitt available to toggle the mast partner lock closed. In practice this is true.

The use of polycarbonate (Lexan and other brand names) for the extensive windows was problematic.
The material itself if brutally strong, much more so than plywood of the same thickness. You can hit it with a framing hammer and it won't break. But it is difficult to affix to a wooden structure because its thermal expansion rate is large. Bob Larkin has done some great work on this and posted useful information on his Birdwatcher II website -- which I did not see until much later. I just drilled oversize holes, almost a quarter inch. They require some sort of washer, and I used faucet stem washers from the plumbing aisle. They work and are cheap, but crack after a season. I need to find something better. The fasteners, about one every 10 inches, hold the polycarbonate against weather stripping. In practice, the assembly is not entirely tight and will seep if you heel the boat right over so the windows submerge. I am not quite comfortable with the strength of the windows still.

The plans call for polycarbonate on aft sections of the top deck as well as the sides. This overhead window is for keeping an eye on sail trim. I chose to use plywood down the whole top deck for a number of reasons. First, sitting in my unfinished boat, I realized that the sails would be easily viewable on one tack without a window, and on the other tack just by leaning forward and having a peek. Besides, this is a cruiser, not a racer. In a ten-hour day, you won't want to watch the trim that closely, believe me. And once you know the boat, you can feel out-of-trim in the seat of your pants. The plans specify plastic on the angled part of the top deck too, but these areas are so tiny that the windows add little to the view. Second, using all wood on the top would increase the strength enormously. Third, there seemed no good way to make the top very watertight where plastic met plastic. Fourth, the top is where you lash the rig at night, where you cook and fillet fish and sometimes stand. It takes a beating. Finally, it seemed the helmsman would be happier without the sun beating on his head. All these things have proved true in actual practice.

The last consideration for the polycarbonate: how dark should it be? The stuff is very expensive, so you don't want to buy it twice. Some people have used it clear, or just barely tinted. Aesthetically, I much prefer the darker look, about as dark as a pair of sunglasses. It makes the boat look all of a piece. In practical terms, it affords more privacy. A strong tint hides the blemishes that polycarbonate gets as soon as you start using it. You might worry that the dark stuff will impede the view, be a disadvantage in low light. On the contrary, we just don't realize how terribly bright it is outside, especially over water. It is very relaxing sailing behind strongly tinted windows. In fact, they don't seem strongly tinted at all, but just right.

Two other small changes. I did not build the integral wooden anchor chock on the bow as shown on the plans. It just looked too complicated, would take a lot of upkeep, and metal anchor rollers are cheap and easy to buy. I built both the stem and stern as Phil Bolger specifies on so many other boats -- but not this one -- with a true stem or stern piece inside the hull panels, and false ones screwed to them outside. The drawn ones were more complex in order to be more economical of lumber.

As for the Birdwatcher's oar ports, I bought ready-made ones from a chandlery, which seemed the easiest route to leak-proof assembly near the waterline, plus I could see through them. These opening ports would turn out to be useless for their stated purpose -- this boat is just too big to row effectively. I had read as much before building but, as a competitive rower, I felt like I would be capable. In practice, rowing this boat is demoralizingly difficult, especially from the position Phil Bolger specified. You are so far aft that the boat is uncontrollable in any kind of cross wind. Even in a flat calm, the boat tracks very poorly. I think two rowers standing fore and aft could handle the boat in some wind, but that would mean four long oars and locks, which take up a lot of room in a small boat and add up in cost. I will return to this topic later, but want to introduce it now in case anyone who reads this is about to install oar ports. At least hold off awhile, because the whole subject of auxiliary power in this boat has been the subject of major re-thinking by Phil Bolger himself -- he drew Birdwatcher II to address this issue. And that, too, will be addressed in a later post.

My ports may be useless for rowing, but they are invaluable for ventilation at night. You can have them wide open in a pounding rain and not a drop comes aboard. You can wake from sleep, prop up on one elbow and get a quick look out to check your anchor is holding, or what the overnight weather may be doing.

Finally, I built some handsome little cupboards for stowing small items and installed these at the middle frame position, at the widest part of the hull. Fortunately I made them removable, because they were useless. I failed to consider that the middle frame is also the deepest part of the boat and thus where the bilge water gathers. If you have cabinetry there, rainwater or spilled tea runs right underneath and can't be sponged up. They also take up a cozy space right next to the helmsman where someone could snuggle in,  thus diminishing the romantic capabilities of this boat. Maybe the idea of sailing with your arm around someone has no appeal for you. But have a thought for the future generations who will inherit your boat!

No, I think this boat is too small for furniture. I have found it much more practical to load the boat with Rubbermaid tote containers. These can be wedged into place for sailing amidships for sailing, then re-positioned for camping afloat. If you camp ashore, these boxes are essentially rain-proof and damp-proof.

Saturday, January 9, 2010

The practical cold-weather shop

It was January 1, 2005 when I started building my Bolger Birdwatcher. While my wife and teenage children slumbered away the New Year's revelries of the night before, I went out to my shop and started laying out the pieces for the four frames that run down the hull like spinal disks. I had the radio playing while I worked, and reports came over the Canadian Broadcasting Corporation network in the aftermath of The Indian Ocean Earthquake of Boxing Day, 2004. The death toll mounted with every news break -- 4,000 became 40,000,  became 90,000. The number would climb to 230,000 souls eventually. The spicy smell of the mahogany boards being cut filled the shop and reminded me of journeys I'd made in the tropics. I thought how absurdly lucky I was to be building a boat in a safe, warm room at my northerly latitude while families, villages were being destroyed somewhere over the horizon. 

My backyard shop was not big enough in which to build the whole boat. The plan was to start with the smaller bits -- frames, rudder & tiller, centreboard assembly, etc. -- while I looked for space to rent. This is a standard procedure for building an airplane, and I would recommend it to anyone. You get your feet wet at minimal cost in materials and time, make progress and build confidence a step at time. When the fiddly bits are needed, they are ready to install. However, it may well be that you don't like boat building after all, or that your free time is not what you hoped. You can always sell or donate small, finished pieces to the next builder and feel good about it. But a half-done hull is usually doomed to rot. 

Via classifieds, I found a large two-car garage to rent not too far away. I spent (ie. wasted) a lot of hours going to and from that shop, and nothing would have sped up my building more than having a place to work a few feet from my house. But I didn't. The rented place had smoothly operating, powered overhead doors, enough electrical outlets, and an even concrete floor. It had been used for car repairs, so I spent a day cleaning it up and taking a load of old parts to the metal recycler. One of the orphaned items was a large green upholstered chair, which some builders call a weeping chair or thinking chair. I got to know mine well, on both counts.

The shop was nearly 28 feet deep inside, which seemed ample for a 24 foot boat. However, it was just barely enough. I had not considered that curved assemblies, like gunwales, are longer than the actual boat they adorn. I was lucky that all the parts for the Birdwatcher could be laid out straight within the walls I had rented.

The shop was unheated but well insulated, important when you live at 53 degrees north latitude and the winter temperature can dip to -40 C, and is typically -20 C most nights (ie. below zero Farenheit). Indeed, I would say my most pertinent advice for building relates to coping with cold temperatures, something that the literature of boat building does not address. A cold shop in Maine or the Pacific Northwest would be warm by my Canadian prairie standards. 

I bought an inexpensive ($150) kerosene heater with blower and large fuel tank, and plugged it into a thermostat unit I put into a surface-mount electrical box and hung from a nail. The rig could heat that large shop to a comfortable working temperature in under 15 minutes, but it fouled the air badly. Because the shop was so well insulated, I found that I could run the shop up to temperature and a little beyond, then open one or both doors briefly to freshen the air. I also kept three 500 watt halogen work lights running. I needed the light, and their waste heat kept the kero heater from cycling on too often. But when it was bitter cold outside, it got harder to balance warmth and fresh air.

If I did it over again, I would buy a heat-exchanger type construction heater, and temporarily rig up a proper vent to the exterior using an entry door opening if I could not cut a hole in the wall. It would cost about five times the price of a portable heater, but you could sell it afterward. Buying jugs of kero was a hassle; it was expensive and local shops ran out. Well, there are many routes to good shop heat. Regardless, I think you need to be able to achieve 15 C (60 F) easily, whether you are working under tree in Florida, or in your Helly Hansen woolies and Sorel boots in my neck of the woods.

Boat-building typically requires the glueing up of very long pieces -- gunwales, chine logs, and planks. I found that a narrow, temporary shelf built along a wall was a great place to scarf together long items. You could clamp or screw work into position, and things would stay out of the way of other jobs while the glue set up. Set-up generally requires room temperatures for 24 hours. Rather than keep the entire shop heated for that long, I found that glue joints could be kept warm by aiming a 500-watt work light up at the shelf from below, and trapping the heat with a stack of insulation batts over the workpiece. You have to be very careful of fire risk with powerful lights -- especially, don't use extension cords for this technique. By careful positioning and some tests with a household thermometer under my "glueing blanket," I could keep glue joints at room temperature overnight even if the rest of the shop was colder than charity. 

That about does it for the description of my shop set up, seen in the picture. The hull of a boat comes together quickly, and by the end of January I thought I would be ready to launch come spring.

Trial by design

During the decade between receiving plans for the Birdwatcher and the New Year's day, 2005 when I actually started building, I was not entirely idle. I gathered a library of boat-building books and read them many nights after my kids had gone to sleep. Amassing the skills to boat-build is something we all do in a different way, starting from different points, and I won't belabour that here. But the long gestation period meant I had plenty of time to scrutinize the Birdwatcher plans for failings, flaws, shortcomings, and maybe find something else to build. To make it a contest, I actually bought plans for a different boat, a more conventional design called Mist from Karl Stambaugh. The Birdwatcher would survive this long ordeal.

My criteria: I wanted a boat that could sail shallow and take the beach, could be trailered readily, was safe and seaworthy. The mission was to sail the many big lakes accessible to us here in Canada. Canoes are at their worst in big open water. Kayaks are somewhat cramped and none of my friends have one. A sailboat was the thing, if it be the right shape. All these are fairly standard criteria for lake sailors. Since a lot of our lakes here are quite remote, I also wanted my boat to be low-tech, repairable in the field as much as possible, especially the rig.

Apart from the mission requirements, I also wanted a boat as a platform for experimentation. Living where I do, I had never seen a boat with a four-sided sail except in pictures. I wanted to play with different rigs, leeboards. This seemed to demand an open boat, so that masts could be positioned fore-and-aft to suit. I had crazy ideas, like a pedal-powered jet-drive auxiliary. I wanted a boat that could be shipped overseas in a container, because I had this fantasy of sailing Lake Baikal in Siberia.

Phil Bolger's Birdwatcher met all these criteria. It was as shoal-draft as a freighter canoe, light and trailerable and so on. As for experimentation, that open slot running the whole length of the boat just invited creativity. You could place the masts anywhere, and partner them anywhere along the coaming with ease. The boat was open, and yet its top structure gave it most of the qualities of a cabin type. Leeboards, if it came to that, seemed like they could be hung easily from the flat-top deck. The auxiliary power -- oars -- did not frighten me, for I was a competitive rower.

My reservations about the Birdwatcher were mostly aesthetic. It is unusual looking, and that's a fact. I have an aversion to looking like a fool, though that has not stopped me looking like one many a time. I did not want my homemade boat to look like one too much. I gazed at Karl Stambaugh's Mist longingly, like Archie upon Veronica. I knew it was a solid design, would work well in all the traditional ways, would turn heads with its beauty. But there would be no fooling around with mast placement on a such a traditional design, no leeboards. Birdwatcher was unusual, yes, but not absurd. It had a alien beauty, but beauty anyhow. I was obsessed with junk rigs at the time and decided she would look great under one. Above all, she was an experimental type herself, which seemed an invitation to break rules. 

In the end, I did what Phil Bolger would do and let form follow function.  I started gathering material to build a Birdwatcher. 

Friday, January 8, 2010

Back in 95

I've wanted to tell my story of building, sailing and customizing my Bolger Birdwatcher for a long, long time. It would be nice to have the details laid out in some kind of order. And I owe the boatbuilding fraternity some record of my doings, since I could not have accomplished many of those doings without a lot of help from all over. I will forego the usual excuses. Let's just say that today, this -18 C January day, is the day.

My life intersected with wooden boats in the early 90s. Odd, because at the time I flew airplanes for fun and thought incessantly of building one. I had a set of plans from a Canadian designer and was just about to roll up my sleeves. Just then, an acquaintance of mine who had recently finished his own airplane was killed when his handiwork broke up in flight. It was determined that the design itself was flawed, but that there had been building mistakes too. I was a good pilot. But the accident made me question if I really wanted to test my building skills in that no-margin-for-error way. It seemed more stressful than fun.

One day I chanced upon a copy of the American magazine Woodboat and found that not only were boats just as sculpturally interesting as airplanes, the lexicon used to describe them was rich and mysterious. As a writer, it is impossible not to be lured by words like keelson, abaft, drogue, mizzen, binnacle, and so forth. Beyond the lovely jargon, the pieces in Woodenboat were somehow beautifully written, how-to pieces crafted into tales. I was drawn to wooden boats by language more than anything. As for getting killed in one of my own contraptions, it seemed less likely to occur afloat than aloft. (Pause while I touch wood.)

You don't dig too far into the modern wooden boat literature without encountering the words of Philip C. Bolger. I don't remember which of his writings I first found, but I do know I read everything he had to say about boats in short order once I did find him. A good writer can make the most arcane topic universal, and his self-critiquing style of boat prose was unlike anything else I'd read. Naturally, I came across his introduction to the Birdwatcher, design number 496, and this iconoclastic boat seemed to embody a very original kind of thinking.

I am drawn to classic lines, traditional beauty, and wooden boats have plenty of that. The Birdwatcher was something else again, call it what you will. But her designer made such a compelling case for her, and the way function drove her form was intriguing enough to make me want to build her just to see if the Old Man, as I came to think of Phil Bolger, was right. Moreover, she fit the bill of criteria I had set for the kind of boat I wanted to build, a topic I will address in the second post.

And so I sent a money order off for the plans. They arrived ten days later in a mailing tube with the rubber-stamp logo of Phil Bolger and Friends on the outside and a hand-written letter from Phil himself inside. He thanked me and said that, if my project "should go ahead," he would appreciate it if I let him know. That was in 1995. It was ten years later when I wrote back.