Description
Sikaflex 291 LOT Slow Cure Adhesive/Sealant White | Boat Supply Store
Address complex bonding applications and humid environments with Sika Sikaflex® 291 LOT, a slow-cure polyurethane elastomeric sealant providing an extended open time of up to 60 minutes for precise alignment. This marine-grade formulation adheres robustly above and below the waterline, maintaining flexibility after cure and offering saltwater resistance. It is NSF approved for potable water applications and USDA approved for incidental food contact, making it suitable for diverse marine projects.
Key Features
- Extended Open Time: Facilitates precise alignment and complex bonding without premature curing.
- Marine Grade: Specifically engineered for rigorous saltwater environments.
- Non-Sag System: Maintains bead integrity for vertical and overhead applications.
- Above & Below Waterline Use: Versatile application across the entire vessel.
- Saltwater Resistant: Endures continuous immersion and exposure.
- Paintable & Sandable: Allows for aesthetic finishing post-cure.
- NSF & USDA Approved: Certified for potable water contact and incidental food contact.
- High Strength & Flexibility: Forms a durable, elastic bond resistant to vibration and stress.
Specifications
| Product Specifications | |
|---|---|
| Brand | Sika |
| SKU | CWR67313 |
| MPN | 90925 |
| Formulation | 1-component, moisture-cured polyurethane elastomeric |
| Cure Type | Moisture-cured |
| Open Time | Extended (up to 60 minutes) |
| Application Temperature | Recommended 50°F to 95°F (10°C to 35°C) |
| Cure Time | Tack-free: 30-60 min, Full cure: 24-48 hours per 1/8 inch (depending on conditions) |
| Hardness (Shore A) | Approx. 40-45 |
| Tensile Strength | Approx. 2.9 MPa |
| Elongation at Break | Approx. 400% |
| Water Resistance | Excellent |
| Chemical Resistance | Good resistance to water, salt solutions, weak acids and alkalis |
| UV Resistance | Good |
| Adhesion to Substrates | Excellent to aluminum, GRP, wood, steel, many plastics |
| Paintability | Yes |
| Sandability | Yes |
| Approvals | NSF approved for potable water, USDA approved for incidental food contact |
| Color | White |
| Container Size | 10.3oz (300ml) Cartridge |
Who This Is For
Marine professionals and dedicated DIY boaters requiring a high-strength, flexible, and durable adhesive and sealant. It is particularly beneficial for those undertaking complex installations or working in challenging high humidity or heat conditions where extended working time is critical.
How It Compares
| Feature | Sikaflex 291 LOT Slow Cure Adhesive/Sealant White | Competitor |
|---|---|---|
| Open Time | Long | Approx. 1 hour, Approx. 1 hour |
| Below Waterline Use | Yes | No, Yes |
| Flexibility After Cure | Permanently Elastic | Flexible, Rigid, permanent bond |
| NSF Approved | Yes | No, No |
| USDA Approved | Yes | No, No |
Common Concerns Answered
Does the 'slow cure' mean it won't be durable?
The 'slow cure' refers to an extended open time, not reduced durability. Sikaflex® 291 LOT achieves a strong, elastic, and durable bond that is permanent once fully cured, while allowing ample time for precise application.
Is cleanup difficult?
Prompt cleanup immediately after application is key. Use an approved solvent like Sika® Hand & Tool Wipes or isopropyl alcohol. If allowed to cure significantly, removal becomes more labor-intensive.
Will I need a special caulk gun?
A good quality, heavy-duty caulk gun is recommended for optimal dispensing and control, especially with high-viscosity sealants, ensuring a consistent bead and efficient application.
Frequently Asked Questions
What is Sikaflex® 291 LOT used for?
Sikaflex® 291 LOT is a versatile adhesive and sealant used for bonding and sealing various marine components, including deck hardware, hull fittings, rub rails, windows, and hatches, above and below the waterline.
Can Sikaflex® 291 LOT be used above and below the waterline?
Yes, Sikaflex® 291 LOT is specifically designed and approved for use in both above and below the waterline marine applications, offering excellent saltwater resistance.
Is Sikaflex® 291 LOT paintable and sandable?
Yes, once cured, Sikaflex® 291 LOT is paintable and sandable, allowing for seamless integration with existing finishes or preparation for further coatings.
What is the open time for Sikaflex® 291 LOT?
Sikaflex® 291 LOT offers an extended open time, typically up to 60 minutes at 73°F (23°C) and 50% relative humidity, allowing for precise positioning and adjustment of bonded parts.
Is Sikaflex® 291 LOT suitable for humid climates?
Yes, its slow cure formulation makes it particularly suitable for humid or hot climates where standard fast-curing sealants might skin over too quickly, requiring more controlled application.
