Stem to Stern: Flipping Hulls

Stem to Stern: Flipping Hulls

Michael Rybovich tells all about the art of hull flipping.

Few things garner more interest, or video, than turning a boat’s base upside down.

For most boat builders, giving tours through their facilities to people over the course of their career is just part of the job. What we do seems to fascinate an awful lot of curious folks. Most visitors have a lot of questions, and we do our best to politely accommodate them. When a new visitor strolls through the yard and observes the boats under construction, one of the most frequently asked questions is, “Why is that hull upside down?” I usually reply with something like, “Damn, I guess we read the print wrong,” or “Oh my gosh, you’re right! Let me find out,” in an attempt to break the ice. It is a great question and one that begs a thorough explanation.

With each new build, we increasingly incorporate state-of-the-art techniques into our construction, all in the interest of making our boats as strong, light and as durable as modern materials will allow. When it comes to the foundation of the build, the hull, we still employ what has come to be known as the “cold-molded” or “jig-boat” method. A temporary skeleton of lofted frames is set up on the floor on stations relating to the shape of the hull and the location of key bulkheads in the boat. Permanent and temporary structural components are placed into this jig, forming an open male mold of the hull, upon which opposing diagonal layers of planking are applied with mechanical fastenings and adhesives. The hull is then sanded, and resin-impregnated fiberglass is applied to the hull as a water-tight, structural skin. This process requires many hours of cutting, fitting, fairing and gluing, which is made much easier if gravity is working for us. Setting the jig up upside down allows us to partner with, rather than labor against, Newton’s elementary force.

Before the development of cold-molding, traditional wooden hull construction began when the keel was set up on the floor, establishing the centerline and backbone of the boat. The term “laying the keel” refers to just that. After the frames, stem and transom frame were set upon and bolted to the keel, the chine log and the sheer clamp were installed, and the structure was ready to be faired and planked. Linear planks were fastened to the frames in a single layer, fit and stacked on one another with a process known as “spiling,” and then edge glued together or caulked with cotton and seam compound between the planks. This old-school method is known as Carvel planking. In our yard, before the conversion to cold-molding, once the sides were planked, the hull was rolled over to make it easier to plank the bottom, and then rolled back up-right when the bottom planking was complete. Two flips of the hull vs. one with cold-molding.

In the days of Carvel planking, our average boat length was between 35 and 45 feet. The beam of the hulls did not exceed the overhead height in the old east sheds, so the boats were flipped inside, using four chain-falls (hoists) hanging from the steel I-beam rafters, much the same way many builders do today, rolling inside a Travelift. It was a simple process, requiring a man at each chain-fall and one man, usually my Uncle Tommy, observing and coordinating the operation. Spectators included the owner, if he or she was in town, the captain and the yard employees. Over time, the new hulls were set up in the northwest shed, which had more overhead clearance and pitched steel rafters. The largest boat flipped inside the northwest hull shed was a cold molded 60-footer in the early 80’s. She had a 30-inch skeg, per the captain’s spec, and while she was rolling, the aft chain slipped off the end of the skeg. Hearts stopped, grown men screamed like sixth-grade girls at a Taylor Swift concert, and because I wasn’t smart enough to run, I was left holding the chains while my self-preservationist crew scattered. When all had regained composure, we continued the flip with no harm done. Immediately after we got her blocked down and leveled up, I carefully scurried up to Grandma’s house to change my pants.

Several years later, we were building small boats again as Ryco Marine, in a warehouse south of the old yard. Dad and our mechanic/electrician, Curt Wills, were playing around with a model hull I had made for test-towing, when they dreamed up an idea about how to flip the 32-foot hull we were planking. Historically, Dad’s ideas were practical and logical. This one seemed not only unconventional but a little scary. The idea was to pick the inverted hull up with a crane by her bow at the top of the stem, stand her straight up, set her stern down on wheeled dollies, and roll her aft and upright and as the crane paid out the cable. He demonstrated it with the model as I protested and presented a case for him to seek help at the mental health center on 45th street. Curt laughed, escaped to his bench, and began fashioning a lifting bar out of a length of steel angle to bolt across the sheer clamp and breasthook. Dad and I went head-to-head, as fathers and sons often do, until he convinced me to try it. What could go wrong? As a safety measure, we ran a chain and a come-a-long down from the lifting bar at the stem to a steel pipe through the forward end of the main inboard stringers. When the day came to flip the hull, I prayed to the Sea Gods and off we went. The process actually worked well and, except for the dollies at the stern nearly running away from Marty and me as we set her down, it was easy-peasy. Over the next few years, we flipped six hulls up to 38 feet this way without a hitch. After each flip, Dad looked at me with his gotcha wink as if to say: “How ‘bout that, kid?”

Tradition meets technology when it comes to hull flipping; the result is something you should check out on the builder’s YouTube.

The seventh hull was a 43. The hulls were getting longer and heavier and standing a 43 on end was a whole different animal than doing it with a 32. When the time came to flip that hull, Dad was up at his place in Southwest Harbor for the summer. Marty and I discussed the flip with Richard Wolf, our friend and local crane operator who had flipped all six of the prior boats. The three of us agreed that it would be easier and safer to flip the boat in a conventional manner on her longitudinal axis. We rigged her on a single crane that had a main and auxiliary winch with spreader bars and straps. The flip was easy and uneventful. After we got her back in the shed and leveled up, I called Dad to let him know that all went well. When I told him how we flipped her, he snarled and told me I was a chickenshit. Apparently, logical deduction had returned to his arsenal. He gradually came around and from then on, we flipped with straps and spreader bars, eventually going to two cranes as the boats increased in size and weight. I have always believed that if one is going to lift large, expensive objects, one should try to lift as little weight as possible. When we flip our hulls, the jig and all temporary hull components have been removed. This also gives us a chance to weigh the hull itself. Some builders flip them with the jig still in the assembly. To each his own.

For the last 25 years, when it comes time for rollover and lifting heavy things in general, we have worked exclusively with Beyel Brothers Crane and Rigging. Kyle Bennett or “Kyle from Beyel,” as he known to most, has been with us to conduct the “orchestra” on all but one. He is a big man and doesn’t take any B.S. from his operators or our crew. He also has to contend with the spectator element. I guess there are no secrets anymore. Social media has seen to that. With these big boats, there is always a tightening of the muscles in your aft bilge, and you want to be on your game. Somehow, on the morning of a flip, strangers appear in droves to witness what they think will be an experience better than sleeping with their favorite movie star. They walk around the yard, searching for that perfect camera angle and, like race fans, try to get close to the action. Kyle will have none of that. This is his baby and distractions are not helpful. We place the straps under the hull on the transverse braces while Kyle and his crew set the cranes and spreader bars. The operators give us the weight of the rigging so we can subtract that from the lift to get the weight of the hull. Cables come tight and Kyle conducts the flip with hand signals to the operators, like Bernstein wielding his baton at the woodwinds, brass and strings. In a few minutes, she’s right side up and the “hullbillies” haul her back in the shed. Kyle and I share a joke or two and reminisce as the oilers pack up the cranes and rigging. We’ve been doing this together for a long time. Such a simple, anti-climactic event—all the work is in the foreplay. The spectators begin to wander off in search of a more fulfilling way to enjoy the rest of a good day. “Is that all there is?” they ask, like they need a cigarette. I walk the crane invoice back to the office and breathe a long sigh of relief. Chickenshit!

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This article originally appeared in the February 2023 issue of Power & Motoryacht magazine.

Source: https://www.powerandmotoryacht.com/column/stem-to-stern-flipping-hulls

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