Packing & Sealing Tape
What Is Marine Packing & Sealing Tape?
Whether you're maintaining a powerboat, sailboat, or RV, packing and sealing tape is one of the most fundamental yet often overlooked elements of routine upkeep. In the marine world, "packing" refers specifically to materials used to seal a vessel's stuffing box — the fitting that surrounds the propeller shaft where it passes through the hull. Keeping this seal tight and properly lubricated is essential to keeping water out and your vessel seaworthy. Sealing tapes, meanwhile, cover a broader range of waterproofing applications, from RV roof seams and hatches to porthole surrounds and deck fittings.
Why Packing & Sealing Tape Matters
Water intrusion is one of the leading causes of damage to both boats and recreational vehicles. A failing stuffing box, a cracked roof seam, or a poorly sealed hatch can escalate from a minor drip to a serious structural problem with surprising speed. The right packing or sealing tape creates a durable barrier against moisture, UV radiation, temperature swings, and the constant vibration that comes with life on the water or road.
For marine applications, shaft packing materials must be able to withstand continuous exposure to water while maintaining a controlled, adjustable seal around a spinning propeller shaft. Traditionally, flax-based packing has been the standard, but modern alternatives — including PTFE-impregnated braids and moldable synthetic compounds — offer longer service life, reduced friction, and improved sealing performance. On the RV side, sealing tapes need to flex with the vehicle's structure, resist UV degradation, and bond reliably to a wide variety of roof membrane materials.
What to Look for When Buying Packing & Sealing Tape
- Material type: Flax packing is traditional and widely compatible; PTFE-impregnated options reduce friction and last longer; moldable synthetic packing adapts to the stuffing box shape for a custom fit.
- Size compatibility: Shaft packing is sized to match your propeller shaft diameter — always confirm the correct dimensions before purchasing.
- UV and weather resistance: For RV and topside marine applications, look for tapes with UV-stable backings that won't crack, shrink, or peel under prolonged sun exposure.
- Surface compatibility: Different tapes adhere to different substrates — rubber roofing, EPDM, TPO, fiberglass, aluminum, and wood each may require a specific product formulation.
- Lubrication requirements: Some traditional packings require water or external lubricants to function properly; newer formulations like dripless moldable packing are internally lubricated and require no drip for cooling.
Top Brands in Packing & Sealing Tape
Western Pacific Trading is a specialist marine maintenance brand based in Hayden, Idaho, with a focused product line built specifically for boaters and marine DIY enthusiasts. The company offers a range of shaft packing solutions including traditional flax packing, PTFE-impregnated braid, and their Drip-Less moldable packing — a clay-like compound that molds to the inside of the stuffing box to create a permanently lubricated seal without requiring water for cooling. Their GTU (Graphtex Ultra) shaft packing rounds out a lineup engineered for durability and long service life across multiple boating seasons.