Even if your boat has no carbon-fiber parts–let alone a carbon-fiber toilet seat–you might find good use for West System’s carbon tape.
According to Jeff Wright, a technical adviser for the Michigan-based company, carbon tape is ideal for adding stiffness to parts of a boat that may have been underbuilt, such as hatch covers or longitudinal stringers. Like fiberglass tape, carbon tape is applied using epoxy; unlike fiberglass tape, which is generally woven in two directions, West System’s carbon tape is unidirectional. All the fibers point the same way, so the tape only adds strength in that direction. Like the wood grains in a 2×4, the carbon fibers in the tape are strongest when they run parallel to the force being applied. “Carbon tape is great for adding tensile strenth and tensile modulus (stiffness),” says Wright. “Think of it this way: If you were to take a single carbon fiber and pull on it, it would be plenty strong. But if you were to push on it from the side, it’s going to bend.”
Because the tape only “works” in one direction, it’s important to consider the load paths involved before reinforcing something with unidirectional carbon tape. If the forces are acting in two directions, you’ll need to apply the tape along both axes. Avoid situations where forces would be acting at angles perpendicular to the fibers. To stiffen a spinnaker pole, for instance, you wouldn’t want to wrap the tape around the pole in a spiral fashion, but in strips along the full length of the pole. “If you’re dealing with compression forces,” Wright adds, “keep in mind that the epoxy is what’s doing most of the work of preventing the carbon fibers from buckling.”
Although carbon tape and fiberglass are compatible with the same materials, Wright also cautions against blindly using the former in place of the latter. “If something is broken, we’d suggest repairing it using a similar method to how it was built. If you just throw carbon fiber down in place of fiberglass, it would be like installing an aluminum plate in your deck–it’s going to create new stress concentrations.”
To make the tape easy to work with, West System adds a polyester fill thread that prevents the carbon fibers from going out of alignment when soaked with epoxy. Carbon tape comes in widths of 1.5 inches or 3 inches at lengths of 12 feet or 50 feet, with prices ranging from $49.40 to $169.05.