A Rope Attachment and Reinforced Joints.

Working inside his boatbuilding shop in Västervik, solo sailor Sven Yrvind begins outfitting his experimental plywood test boat with protective hardware and heavy-duty lifting points. To safeguard the bottom of the hull during transport and launching, Yrvind shapes and fastens an iron runner along the keel line. The metal strip bends into place with two fingers and extends all the way to the stern, shielding the bottom whenever the boat slides off a road trailer.

Sharing each technical stage on his Sven Yrvind channel, the Swedish mariner moves forward with structural preparations on the 4.8 meter hull. Before the boat can be moved or rigged for testing, he must engineer a balanced lifting arrangement capable of handling the vessel’s weight without stressing the wooden joints.

Locating the Center of Gravity and Drilling Pipe Housings

Determining the balance point is critical for safe hoisting. Yrvind calculates the center of gravity just behind the middle of the boat at 53% from the front, approximately 220 cm from the back. To create dedicated hoisting channels, he prepares pipe sections to guide the lifting ropes through the interior box structure.

Drilling the pass-through holes through the structural timber tests the shop’s tools. When a cordless battery drill stalls under the load, Yrvind upgrades to a heavy corded machine powered directly from the mains. Reflecting on the demanding task, Yrvind explains that “This battery machine was not strong enough, but I have a big one with from the wall electricity” to bore the holes through the timber assembly.

Potting the Pipes and Fitting Dual Rope Grips

To ensure maximum adhesion between the metal pipes and the wooden box, Yrvind scuffs the outer pipe casings using a mechanical grinder equipped with coarse 36 paper. The abraded texture provides a strong mechanical tooth for the bonding agent. Thickened epoxy compound bridges the clearances around the drilled holes, creating an impermeable structural pot.

Praising the versatile gap-filling properties of the resin, Yrvind notes that “Epoxy wonderful thing, you know, with this uh thickener thing, you know, it makes things fit every everywhere” across uneven workshop assemblies. Once the epoxy compound cures, he cuts the sleeves flush with the hull and countersinks the openings. Beveling the rim ensures that the rope does not chafe under load. By installing two separate through-hull pipe points, Yrvind can rig two ropes to alternate his grip and maintain balance along the center of gravity.

Reinforcing Wooden Joints with Fiberglass Tape

With the lifting sleeves secured, Yrvind inspects the corners and joined plywood edges. Knowing that simple woodworking adhesive alone cannot withstand the concentrated lifting tension, he marks the seams and wraps them with glass fiber tape. Applying resin and composite fabric across the seams reinforces the joints before hoisting begins.

Surveying the reinforced corners, Yrvind explains that “now it’s also glass fiber all around to keep it together” so that the wooden seams do not pull apart under dynamic loads. The cured composite corners provide the rigidity required to move the test hull safely toward its next stage of outfitting.

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