Sheeting To The Rail
Mayan was originally built with some form of inboard sheeting for her jibs, fisherman staysail, spinnaker, and gollywobbler. That was the tradition back in the '20s when Alden designed her and that is the way the Tewie's Dockyard built her in 1947. But over the decades whatever sort of sheeting she had disappeared and was replaced by the newer idea that one run a track along the top of the rail allowing the sheet points to be adjusted by sliding a car along the track. You can see the bronze track and cars with a sheet lead through them in the picture on the right. The genoa sheet is lead to the block ahead of the mainmast shrouds and the advance staysail is lead to the block closer to you aft of the shrouds.
There were two problems with this approach on MAYAN. First, she is a beamy boat. Alden made this choice when designing her so that she could carry more passengers in comfort and so she'd stand up without heeling much in a blow. Her broad beam makes her quite stiff despite the fact that she has only a shallow and relatively light keel. The difficulty is that the beam is wide enough that the sheeting angle is too far outboard and as a result one can't trim the sails in tight enough to allow MAYAN to sail to windward at her best. After doing a bit of calculating, we determined that it would be best to have the sheet points moved about two feet inboard from the rail to get the correct sail shape.
Second, when sails flog or flap they jerk quite hard on the blocks which as riding on the rail. Similarly, when sailing in heavy weather there is a tremendous load put on the sheet and therefore on the rail when gusts hit or when a wave top fills the sail with water. In that case, the bulwark frames and bulwark planking have to carry the load. This is something they weren't designed to do. In the first few years of our sailing MAYAN hard in the strong winds of San Francisco Bay we discovered that the bulwark frames had been moving a little, indicating that they were overloaded.
In the picture above you can see MAYAN beating past Alcatraz Island in nearly 30 knots of wind still carrying her largest jib. the strain on the rail in these conditions is substantial and well beyond the use she had seen in her earlier life in S. California. It was time to do something about it.
Sheeting Inboard
Once we'd decided to move the sheeting inboard we started exploring various methods. Some recommended simply moving the track off of the rail and attaching it to the side deck, where there is plenty of space. As someone who has had both little toes broken by banging them into objects mounted on the deck, I was completely unwilling to clutter up MAYAN's side decks with bronze tracks with sharp edges and cars running on them. We turned to the oldest way of attaching the sheets and adjusting their angle to get the sail to set correctly. Our guess was that this was used on MAYAN when she was built. Returning to this old technique is particularly interesting because fixed sheet points with barber haulers used to just the sheet lead is now the very latest technique used on the fastest racing boats.
The first step was to remove the track from the teak rail cap. Once that was done we took a good look at the wood, which we believe was installed sometime in the '60s, and decided "While we're in here" we might was well put new rail caps on the boat so we can varnish them. Age has rendered the old teak so badly damaged that we couldn't bring the wood back to a level that would support varnish, and the number of wood plugs we'd need to put in was astounding. So, we removed the rail caps and Wayne announced: "I still have the teak I ordered in 2004 when we rebuilt the hull. It's ready to go." as he wandered off to start locating the raw planks of teak for the new rail caps in the wood shed.New Rail Caps
(We'll get back to the inboard sheeting once we get the rail cap completed.)
Once all the rail caps had been removed, which required removing hundreds of wood plugs and backing out the bronze screws, we set about filling all the holes in the bulwark and the bulwark frames. The tops of some of the frames had some minor water damage which was treated with epoxy and then all the frame ends were brought up to the correct height with a hard compound of epoxy and filler.
As is typical of Wayne, as soon as the rest of us went to work on the rail cap, he dragged a large teak plank into the shop, built a form of the curve of the transom rail cap which stretches across MAYAN and arches up in the center, and then clamped the raw teak plank to the form. "What's that for?" I asked. "This will let the teak plank get used to the idea that it's going to be bent like that for the next thirty years." Wayne replied with a grin. We lifted the plank clamped to its form onto a shelf in the back of the shop and set about the rest of the work. When we retuned a few weeks later, it was already "used to the idea" of being bent and didn't even try to straighten out when we pulled off the clamps.
Once templates had been made and the teak milled and rough sawn to shape, the joints were cut between the sections of the rail cap. The picture on the right shows a locking scarf. Three things are important about the way Wayne does this. First, there is the lock in the center of the scarf, which keeps the wood from moving fore-n-aft as it swells and shrinks with moisture changes and as the hull of the boat moves under load.
Second, at each end of scarf he turns the cut to intersect the edge of the rail cap at about a 50° angle. This makes the joint sides thick enough that the thin side won't splinter away during sanding or in the event that something like a block or or oar bangs into the rail cap.
Finally, in four places along the run of the scarf two inch pieces of bronze all thread will be glued into both pieces of the rail cap from the joint side. This eliminates the need for bolts covered with wood plugs to be inserted into the curved sides of the rail cap. Plugs on rounded surfaces, like the edge of a rail cap, have a bad habit of coming out over time. It's good to avoid them if possible.
With the top edge of the bulwark heavily coated orange anti fungal primer the rails start to work their way forward from the transom plank. The rail cap expands to round the shrouds. In the picture on the left you'll notice that the rail is wider as it goes past the mainmast shrouds. The rail cap is set down over the chainplates and caulked into place once screwed down.
Before being screwed in place, most of the rail was shaped with a series of router bits and then sanded to a 150 grit finish while the planks were still on the bench. This saves a tremendous amount of back breaking labor when compared to doing the sanding once the wood has been mounted on the boat.
The process of cutting, shaping, sanding, and fastening the rail caps went relatively quickly. Within a week all the easy parts were screwed down and ready to be finished. But, as is always the case, the difficult fitting came at the corners.
Here are Wayne and Garrett working the complex joint between the transom rail cap and the starboard side rail cap. Like the locking scarf, these joints were reinforced with two inch lengths of bronze all thread which requires more careful assembly but much less work later on.
In addition to the two large sections, each corner of the rail cap has a triangular piece which allows the rail to sweep gracefully from the side to the transom. Fitting this was Garrett's challenge. He did a terrific job and learned a few tricks from Wayne along the way.
The most difficult part, by far, was the tip of the bow. You can see it on the left. Again, the joints were reinforced with bronze all thread and glued with epoxy. But the curve of the rail, the sweep of the sheer, and flare of the bow all gather together at this point causing each piece to have sides which were far from square to anything.
After an afternoon of careful fitting, Wayne applied the glue and clamped up the pieces with bar clamps, "c" clamps, a special jig he cut from some scrap, and a trailer load tie-down strap. It all held and was aligned perfectly in the morning when all this bondage was removed.
Because there need to be flat surfaces to clamp against at every scarf and joint, a great deal of hand work was now required to shape the exterior of the rail cap where these occurred. Now came days of that back breaking hand work with everyone pitching in to get the shape just right.
Once shaped the finish work started. In the picture on the right you can see Garrett helping to sand the rail as each coat was applied.
We're taking a new approach with this varnish stack. At the bottom on the raw wood are two coats of thin sealant. It penetrates the wood and stabilizes the natural oils in the teak. Then we apply three coats of West 207 special clear epoxy. What you see in the picture on the right is the shine of the second coat of epoxy. While difficult to sand, the epoxy is extremely tough and will resist chafe far better than traditional varnish.
Finally, we applied 5 coats of a classic spar varnish to provide UV protection for the epoxy and because it yields a beautiful shine. Because the jib sheet tracks have been removed from the rail, one person can sand the entire rail cap in one day. This is more than twice the speed of anyone who had tried it, especially me.
Now back to the Inboard Sheeting
With the rail caps nearly complete, Garrett and Rubin set about installing the deck plates which will hold the eyes and snatch blocks for the sheets. In the picture on the left you can see the bronze pad with its removable eye screwed in, upper left. It will be let into the deck. You can see the diamond shape dent which has been cut into the teak to match the bottom of the pad. It has been sealed with epoxy to prevent rot and the bronze pad will be covered in dolphinite to further protect the wood.
These pads were located approximately three feet aft of the known sheet point for each sail. Then approximately three feet forward of the known sheet point, another pad was installed. Fortunately, this spacing resulted in being able to re-use a number of pads for different sails. As a result, the side decks have a pad approximately every six feet and these pads can manage our entire inventory of sails.
In addition, the pads serve as terminations for the running backstays for both masts.
For each pair of pads assigned to a sail the aft-most pad carries a snatch block which accepts the sail's sheet. the forward pad carries a barber-hauler with a low-friction eye spliced into the upper end. To protect the varnish and more importantly the sailors aboard, the eye in the end of the barber-hauler is run through a soft vinyl tube as shown in the picture on the right. This is expected to reduce the damage done when the sheet is flogging and the eye is swinging around the leeward side deck.
The lower end of the barber-hauler is secured to the pad's screw-in eye with a hobble splice. This splice, which was become quite popular with the adoption of high strength Dyneema single braid lines, works in a manner similar to a line with a rolling hitch tied around it. When the line is relieved of load, one can slide the hobble to make the line whatever length is required. Once the load is reapplied, the hobble will not slide. Aboard MAYAN we mark the barber-hauler lines to that the crew can preset the hobbles to the correct position for each sail.
Of course, adjustments of the jib lead position do require that the load be removed from the jib sheet using this technique, but that was also true of the bronze track and cars which this system replaced. We also sail with a 6:1 handy-billy on deck. It's quite useful for tasks like pulling the jib or staysail sheet down while one adjusts the barber-hauler.
So far, this system has works quite well. We used it while competing in the Jessica Cup in San Francisco Bay and found it to be reliable and easy for the crew to understand. However, one problem was discovered, with the sheet leads inboard where they belong for the best sail trim, the sheet runs directly over the signboards and running lights on the foremast shrouds. Naturally, we found the lights dangling from their wires and bits of the signboards missing entirely. Not everything goes according to plan, we'll need to relocate the signboards to a place out of the line of fire. The fact that the signboards were damaged is great evidence that we've finally got the sheets in the right places, looking on the bright side.
Simply beautiful, albeit tricky, workmanship
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