3M
3M 05280 Polyurethane Adhesive Sealant 3 oz Tube White
A polyurethane adhesive sealant for marine use above and below the waterline, curing in 24 hours with a 20-minute application window
- Fast cure in 20 minutes for quick repairs
- Functional cure in 24 hours for reliable bonding
- Works above and below waterline for marine use
- UV resistant and weatherproof for lasting protection
- Sandable finish that will not yellow over time
Marine-Grade Adhesive Sealant
3M 05280 is a one-part polyurethane adhesive sealant designed for marine applications above and below the waterline. The 3 oz tube provides a waterproof, flexible bond that resists UV exposure and weathering. It cures to a white finish that will not yellow like traditional urethanes. The low-VOC formula suits gelcoat, wood, metal, rubber, plastics and fiberglass substrates.
Surface Preparation And Cure Window
Verify that the application temperature sits between 40 and 100 F before starting work. Surfaces must be clean, dry and free of contaminants for proper adhesion to materials such as aluminum, steel, stainless steel, ABS, pine or FRP. The product offers a 20-minute application time and reaches functional cure in 24 hours. California Proposition 65 warns this product contains a chemical known to cause cancer.
Replaces Standard Urethanes For Marine Use
This sealant upgrades from conventional urethanes that tend to yellow, shrink or sag over time. The non-shrinking, non-sagging formula maintains joint integrity in wet environments. The jump is worth it when a flexible, sandable, UV-resistant seal is required for structural bonds on boats or marine equipment. It is not suited for buyers who need a high-temperature adhesive beyond 100 F or a product without Proposition 65 warnings.
Highlights
- Fast cure in 20 minutes for quick repairs
- Functional cure in 24 hours for reliable bonding
- Works above and below waterline for marine use
- UV resistant and weatherproof for lasting protection
- Sandable finish that will not yellow over time
Specifications
| Brand | 3M |
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Questions about this item
What comes in the box and what else do I need to apply the sealant?
The package contains one 3 oz tube of white polyurethane adhesive sealant. A standard caulking gun is required to dispense the product and is not included.
Which tube size should I choose for my project?
This listing is for the 3 oz tube. Select this size for small repairs or limited applications; larger cartridges are available separately if you need more volume.
What does the 4000 fast-cure rating mean once the sealant is in use?
It identifies the product as 3M Marine Adhesive/Sealant Fast Cure 4000, which reaches a functional cure in 24 hours with a 20-minute application window at temperatures between 40 and 100 °F.
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