Tuesday, February 7, 2017
Parbuckle and Launch
No doubt, some people will simply hire a crane—twice, at around $1000 each time. But that seems like a lot of money for 10 minutes of work. On the other hand, 4x4 timbers, carriage bolts, nylon rope and comealongs are quite cheap, and there is a great deal of satisfaction to be had in carrying on such an impressive task without any power tools.
The hull is initially assembled upside-down. A build platform is erected on the ground, allowing for a crawlspace underneath to get inside the hull, and leveled using wedges. The deck is then assembled on the platform, followed by the bulkheads, the interior panels, the sides and the bottom. The entire bottom section of the hull is then fiberglassed. The bottom is sheathed in copper and the topsides are faired and painted.
The hull then has to be flipped right-side-up. This operation is known as parbuckling, and is standard procedure for salvaging large vessels. For example, the cruise ship Costa Concordia, which sank off the coast of Italy when its idiot-captain ran it aground was parbuckled and refloated. That salvage operation cost $1.5 billion—as much as that ship cost to build. But that ship was bigger than Titanic. The cost to parbuckle QUIDNON should be just a few hundred dollars—cheaper than hiring a crane.
The first step is to construct a cage around the hull. Vertical timbers are added to the build platform. Horizontal timbers are blocked against the bottom. All of these are fastened together using carriage bolts. Next, posts are driven into the ground on both sides of the hull, and ropes are attached to the cage. Comealongs are used to lift the hull and also to let it down gently once it goes past the tipping point. A few square bales of hay would be helpful to avoid hard landings. The following sequence of diagrams shows the steps of the process.
Once the hull is right-side-up, most of the parbuckling cage can be dismantled, leaving the hull sitting on a skid. Then the deck and the superstructure can be finished. The deck is fiberglassed and sheathed with aluminum diamond plate. Bulwarks, deck arches and the cockpit are added, along with other essentials such as deck cleats. The hull is then ready for launch. Everything else—plumbing, wiring, engine installation, mast tabernacles, masts and sails, etc.—can be done with it floating at the dock.
The easiest launch scenario involves a boat ramp. Then it’s just a matter of pushing the hull, on its skid, to the boat ramp, by rolling it over logs, and pushing it in the water. But it is unlikely that any given patch of shoreline that’s amenable to having a QUIDNON built on it is going to come equipped with a boat ramp. If the boat ramp is not right at the build site, then the hull would have to be transported to it on a flatbed. Since QUIDNON’s hull is 16 feet wide, it is considered a wide load, and transporting it over public roads would require permitting, a signal car and a pile of cash.
The alternative is to build QUIDNON on the water, and then just push it in. Most likely, the building site is going to be a riverbank of some sort. If there is a seawall and the water comes close to the top of it at high tide, then the hull can simply be pushed over it at high tide. If there is no seawall, then perhaps it can be dug down to a slope, to make an improvised boat ramp, but such activities are often frowned upon because they cause coastline erosion. If the body of water is a tidal estuary, erosion is already likely to be a problem.
A better approach is to shore up the riverbank by dumping riprap to just above the high tide line. (If there is existing riprap, that’s of course even better.) The riprap can serve as a foundation for a concrete launchpad. The launch procedure, illustrated by the following diagrams, involves pushing or dragging the hull, on its skid, to the launchpad. Spring lines are then connected to the transom and belayed at the launchpad. The hull is then pushed past its tipping point. Spring lines are then eased symmetrically, allowing it to slide into the water. Finally, when the transom is already afloat and just the front of the skid remains on the launchpad, a workboat pulls the hull the rest of the way into the water. The skid is then released and retrieved. QUIDNON can then be moved to a dock.
Yes, this does sound rather adventurous for a DIY project, and yes, it is possible to build a QUIDNON at a boatyard that’s equipped with a crane and a travelift, and let professionals handle the heavy moving operations. But the point is, it is going to be possible to build a QUIDNON on any relatively flat patch of land next to water and launch it using nothing more than some hand tools and a few comealongs.