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| This article was first published in Small Craft Advisor, issue # 53 | |||
| In the last issue we completed the
cockpit area, decks and most of the other accoutrements. This brings
us headlong into the daunting task of flipping the hull upside down
for the much needed work awaiting us here. It is a precarious operation
at best, capsizing 300 lbs of slippery boat, and should be done under
complete control. After mentally going through a few hopeless scenarios
we decided to hang the boat in slings from the rafters, Travel Lift
style, and first work the hull up on its side then through the full
180 degrees, taking advantage of the cradling friction of the slings
to control the speed. It worked out remarkably well. The two slings
were standard 1" tubular webbing, such as used in rock climbing,
and they were prevented from slipping off the ends of the boat by
connecting them to each other with light rope. Safely back on the horses, it is now time to make this one smooth hull. If we were grumpy about the endless fuss over nice fillets and perfect paint job inside the boat, don't worry, it was fully justified. That was all just cosmetic nonsense and created solely to please the eye of discriminating onlookers. But now, out here along the chines and on the curving expanses of bottom and topsides, it will actually matter to do a darn good job. Water flows past here. This is where our project becomes a boat and not just a piece of furniture. We need to bend down, squint, feel and caress with attuned eyes and sensitive fingers. The process of producing a fair hull is long and arduous, yet strangely satisfying. In short we will fill holes and dings, round over and fair the chines, keel, stem and transom, tape them, feather the tape edges, fill and fair hollows around scarphs and bulkheads, glass the entire hull (optional, but highly recommended), fill the weave of the glass, smooth the whole affair, install gunwales and keel and finally apply quality paint and brass rubbing strips. Before returning to this somewhat overwhelming list, let us discuss painting and its antithesis, not painting. Some proud builders feel that a wooden boat need to be displayed glaringly so, by sporting acres of varnish. They are seen everywhere, those shiny brown strips of plywood masquerading as boats. Especially the sea kayakers appear to fall in this trap. Wide pieces of plywood are simply not a pleasing representative of our craft, and deliberately drawing attention to them is unestethic . The grain is wildly busy and obviously machine made, scarphs becomes conspicuous , but worst of all, there's just too much of it. Like any truly desirably object, the allure of the hidden is always stronger than the overdone and explicit. So let us agree to paint this one. How we do it will come later. Rounding the chines, stem and other sharp corners are not as easy as it seem. The roundover radius must be consistent, whether it diminish or grow. Our eyes are the best tool here, besides rasps and hand planes. On the stem, that graceful but painfully obvious forward terminus, a flexible batten will help to establish fairness. Bear in mind that fiberglass tape will span all these converging planes, so the roundover must be generous enough to prevent lifting and the much dreaded air pockets. When satisfied, grab a stiffer batten, of say 3 feet or so, and lay it on the hull at potentially troublesome areas, like scarphs and forward where those short strips of glass were applied way back then. Look for hollows and gaps where the batten is bridging imperfections. Mark these and head down to the chandlery to get a pound of phenolic microballoons, This airy powder, when mixed with epoxy, will form an easily sanded paste that will become a stable component over the next few weeks of work. Fill the aforementioned dips with this purple sauce, but bear in mind that microballoons are not thixotropic, meaning they will sag under their own weight. Alleviate this with a spoonful of colloidal silica. While the ooze is curing spend the time making a longboard, the most essential gadget for fairing a hull. It is basically a 20" long by 3" wide semiflexible board with sandpaper on the bottom and convenient handles on top. My latest incarnation is made of scrap 1/4" marine ply and seems to work as well as former, more fancy mahogany versions. In fact make two while at it, and orient the grain lengthwise for maximum stiffness on one and perpendicular on the other, softer longboard. The only real worthwhile sandpaper to use on these tools are durable, hard wearing sanding belts cut open. Coarse and medium are ideal. Wrap the belt around the ends and hold it in place with little through bolted cleats, heads countersunk on the bottom and nuts on top. Handles are fashioned to operators digression. Back on the boat with these new tools we sand the microballoons down to a feather edge patch that neatly fill the disturbing hollows. As we work it down, we constantly check with the batten until all is fair. Next is the job of taping the joints. No fillets required here, but the wire holes and other cavities must be plugged first. We had lots of practice with fiberglass tape earlier on, so this should go smooth. What is not smooth, on the other hand, is the finished tape job and its interface with the surrounding hull. Sanding it all down will just weaken what we just strengthened, so we don't do that, One possible solution is this: With the longboard lightly knock down the most glaring high points, then trowel on a filler coat of epoxy and pure colloidal silica. Sand again, this time with a little more zest. Now come back with the microballoons and a 6" squeegee and carefully feather those edges into the plywood. Sand to perfection, and look back on another week spent on the boat. But we made that tape pretty much disappear. One layer of tape will suffice if we glass the entire hull, which is next. A willing, but not necessarily skilled helper is an asset with this job. We will teach the cheerful assistant how to mix perfectly blended batches of epoxy, while you and I proceed to coat the hull and transom. For an optimal job, make sure the ambient air temperature is dropping during the application and for hours afterwards. Later, when it has cured to the 'green' state, we prepare to glass one side of the boat. First we run a strip of masking tape along the stem and keel precisely where the glass will terminate, ideally an inch or so in on the opposite side. The same on the transom. Then we delicately drape the cloth over one side of the boat, so it overlaps the tape and hang below the sheer. 50" stuff will just fit. Spend some time smoothening it out, but carefully so we don't wrinkle it. Now, with at least a gallon of resin and hardener on the bench, get the assistant going on mixing 3 oz batches. Start midship near the keel line and lightly spread the epoxy out in all directions without moving the cloth. Watch the glass go invisible then possibly come back and recover some goop for distribution further along. When the whole thing is wetted out, proceed to the tedious chore of creating an even saturation all over. The aim is to have the weave show clearly, but not appear starved and milky. After that, wait for the 'green' state and fill the weave with epoxy mixed with colloidal silica to the consistency of syrup. Try to lay down an even coat. Sand when fully cured, but not too aggressively. Trowel on a thin coat of microballoons and sand again (don't forget to do all this on the transom too!). If we have used our critical eyes and fingertips during all these laborious steps, with the aid of low angle light to ensure fairness and beauty, the hull is now nearly a work of art. But likely we have been a little too relaxed here and there, and the result is good, very good indeed, but not perfect. So what? We're amateurs, right? The microballoons are too porous to take paint in an orderly fashion, so, believe it or not, we must squeegee on another thin coat of epoxy to seal things up. Sand this final application lightly. Before painting the hull we install the keel. Like everything else it will be glued on, but holding it precisely where designed while the epoxy set up can be tricky. First the keel is not entirely sawn to shape but rather sprung in place, a fact that requires more than casual clamping pressure. The designer suggest the ubiquitous drywall screws driven from the inside out into the keel. Unfortunately our cockpit is all done and waiting for the awards ceremony, so randomly shooting ugly screws through painted surfaces won't do.. Also some awkwardness could arise from this maneuver, especially if we're short on manpower. We accomplished the same thing with shores from the rafters, a typical and very useful boat shop trick. When dryfitting we discovered that the face of the keel meeting the boat needed a slight hollowing to sit right, especially forward, but that was all done quickly with the help of gouges and small diameter drum sanders chucked in the drill. This is also the opportunity to stick on the outwales, or sheer rubrails. These long and very visible members, seemingly simple in nature, actually takes a bit of effort to get right. First off they are just shy of 18 feet long. If stock that size is not in the inventory, shorter pieces must be scarphed up. The rails that went on our boat was 1¼ tall by ¾ thick, meaning we could rip them out of regular 2X lumber with minimal waste. If we call that good and just stick them on they will visually create the very unfortunate effect of being skinny midships and increase in scantlings towards the ends. Not good at all. Conveniently we also don't need all that heft at the ends, so simply taper the last 5' or so in both planes. Elegant yet simple. Only a few spots along the sheer will accept clamps, so we will use screws driven from the outside to hold them in place as the glue dries. On the Core Sound I found the hard chined hull in need of a little extra trim to look more traditional. The solution, derived from a brainstorm with my friend and fellow boatbuilder Dave Williams, was to accentuate the sheer line with a contrasting color. We glued on a second, smaller rubrail below the first one in a pleasing curve that slightly exaggerated the sheer. Holding it while the epoxy set was challenging. Screws would have nothing to go into, besides scarring an already finished interior. We finally fastened on short battens in the holes already in the other outwale, and where these spanned the new rubrail we inserted a wedge to provide clamping pressure. The space between the two rails, mimicking the shape of a plank in a lapstrake hull will then be painted a dark color. Now the hull should finally be ready to receive the paint of our choice. After deciding on a color (white, off course, but with a slight tinge of cream), the next question is what type of paint? In the previous article I mentioned System 3's unique water based epoxy paint. I still find this product to be one of the best choices, so let us briefly explore its use. The advantages are water cleanup, low VOC's, tough and durable with the potential for a very smooth finish with brush or roller. Since I like the looks of hand painted boats I have never invested in any complicated spray equipment. Some minor brush marks are no problem, yet this paint flows out pretty nice and looks real good in a semi high gloss kind of way. But to achieve acceptable results the conditions must be precisely right, and this is the only major drawback of this paint. A dry and warm situation makes it impossible to maintain a wet line on anything but real narrow planks. For my location I found humidity in excess of 65% to be crucial, preferably paired with moderate ambient air temperature. Being in a semi arid climate, I had to construct a plastic tent around the boat, crank up the camping stove with a pot of water, and choose cool mornings for painting. With this elaborate set-up the paint turned out good results, using a foam roller to spread and a foam brush to tip. Quite a few coats have to be put down for acceptable coverage, but if recoating within 24 hours no sanding is needed. I took advantage of this to quickly build up layers, then did some fine sanding with 400 grit paper before the final coats. Off course we could just have used the oil-based products from Kirby, and possibly avoided a bunch of hassles. But is that how it goes? Or would we just have switched the nature of our toil? Because painting is what it is: A finicky endeavor demanding infinite patience and skill, usually commenced with too high expectations guaranteed never to be met. The result will invariably be an adequately painted boat and a good deal of disappointment. But 99% of the lurkers frequenting our shop still thinks it is nothing short of fantastic. Flip the hull back over, right side up, and paint the decks. Also slap some coats on the rudder assembly, center board and whatever else is lying about. Toss away the nitrile gloves and move on to better and more meaningful tasks. We need a couple of masts. Aluminum might work for the racing crowd, but not on this boat. Due to the severe taper specified in the plans, we went for solid wood spars, glued up of ffive laminates of three quarter inch douglas fir. This chore constitutes an entire lengthy subject in itself, which fortunately is dealt with in many respectable books on boatbuilding, especially the ones by the authors Rössel and MacIntosh. These are volumes worth having any way, so just get them and settle to the fact that a week or more will be consumed, knee-deep in shavings, carving two 19' foot masts and a couple of sprit booms. The punch list is still long. A huge project like this has loose ends everywhere, besides the hourly addition of new items to the list. The scheduled launch day is now an old joke from last month. But, with the creation of the spars, most of the all consuming, crucial jobs are safely behind us. Sails can be ordered and while waiting for the loft to do their part the boat in all its excruciating detail will be completed. Seal the hatch openings, hang the rudder dead center on the transom. On and On. Sand, finish and clean-up. Install the centerboard while making sure that pivot pin won't leak a drop. The application of a specific compound called Dolfinite will give us the best chance of success in that department, and, as we move on to rigging, will also prove indispensable in bedding all the various hardware. Rigging! Ah, yes! This is fun stuff, so directly linked to sailing and being on the water that we almost smell the sea breeze wafting through the dust and shavings. We looked to the plans, but if we've been in small boat before we certainly also thought up a few changes, moved a cleat here, re-lead a sheet there, and added mooring bits on the centerline, fair leads at the sheer. We will start out with the sails laced to the masts and see how that works. After studying the overly complicated centerboard downhaul-uphaul schematic on the plans, we regretted not simply weighing the board with a chunk of lead. Oh well, next time... The mizzen sits smack in the middle of the cockpit, so the various sail tensioning lines cleat right on the mast in an old fashioned, simple arrangement. The main is trickier, being poised as it is out there on the bow. To save our sailor from crawling around on that slippery foredeck, we lead the snotter and halyard back within easy reach, redirecting the lines via cheek blocks on the mast to regular horned cleats just forward of the coaming. The sheets for both sails are specified as "double ended", meaning that each cleat in two locations, to port and starboard. This allows for easy adjustment on either tack and is a real good idea. We furnished the sheets with those spring loaded camcleats, so the sailor can cast off quickly and positively if the boat starts going over. As a footnote to the rigging chapter, and to hopefully provide some inspiration, it should be mentioned that we built all our own hardware for this boat, except the pintles and gudgeons, and the camcleats just mentioned. Plain horned cleats and single blocks are the mainstay of most rigging jobs and both are fun and relatively easy to make. So are fairleads and cheek blocks. It will help to have a small bandsaw with a 1/4" blade and a drill press. With the right choice of wood we were able to make these fittings well proportioned and elegant and still provide adequate strength for our small boats. As some revered designer, maybe Joel White, once said: "..it only has to be strong enough to capsize the boat..." I guess we' re done. Amazing! There it is after years of toil, I mean fun. Launch day is a big, emotional event with a fair bit of nerves
and some anxiety thrown in, especially for the builder. When the
boat quietly slid off the trailer the attendants with any pride
invested in the project quickly scanned the cockpit sole for sudden
pools of water, particularly around the automatic bailer. Some of
us had voiced several good arguments against installing the darned
thing in the first place. But all was good. She floated nicely,
sails furled around the radically tapered mast, sheets reeved and
ready. A few impatient smiles was flashed towards the ubiquitous
cameras and then the carefully selected dream team consisting of
the builder, his son and the only true seaman present hopped in
the boat and back paddled out of the tree encumbered tunnel acting
as launch area. Somebody shipped the rudder, dropped the board and
shaky hands unbridled the virgin canvas.
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