At its most basic, fiberglass tape is composed of twisted glass filament strands. Those strands are woven at right angles, making up fiberglass cloth of specific widths. To keep the cloth from continuously unraveling, it contains selvedge edges.
Fiberglass cloth tapes composition gives it impressive water resistance. If you place the tape on a wet surface, it will resist corrosion and peeling. The tape also effectively wards off chemical intrusion.
Generally speaking, boat builders and repairers use fiberglass tape to reinforce targeted areas that need extra fiberglass cloth. When repairing a kayak or dinghy, a lightweight fiberglass tape is sufficient. If you are working on a larger boat, a knitted fiberglass tape is a better choice.
Cloth fiberglass tape is ideal for beefing up corners and glassing seams throughout a boat. The tape is also an excellent choice for fiberglass repair and tabbing projects. Fiberglass tape is compatible with epoxy, polyester, or vinyl ester resins.
If the vessel contains a cabin, reinforce interior bulkheads with fiberglass tape. On the boats exterior, apply the tape to keels and chines. For a smaller plywood stitch-and-glue boat, apply fiberglass tape over epoxy fillets or use for planking the junctions.
Important Note: We sell a high-quality fiberglass tape that is designed for boatbuilding applications. We do not carry drywall tape, insulation tape, or fish tape.
There are three convincing arguments for using fiberglass tape rather than fiberglass cloth. First, the tapes selvedge edges ensure that the cloth stays intact and does not unravel.
Because tape is available in 2-inch to 12-inch widths, you can choose the tape that is exactly right for your application. For example, narrow tapes wet-out more quickly for small crack and joint repairs. Areas with wider cracks, and spots that need aggressive reinforcement, will benefit from wider tape.
Finally, applying fiberglass tape will be a smoother and quicker process than spreading out fiberglass cloth. With less area to cover, and less fabric to manage, keeping the fiberglass tape on the right track should be much easier.
There are two instances in which fiberglass cloth has the advantage over fiberglass tape. First, cloth is designed for use on large areas of the boat, where tape is impractical for those tasks.
In addition, fiberglass cloth is available in varied thicknesses and weights. This enables you to match the right fiberglass cloth with areas that receive lighter or heavier use.