3M 5200 Marine Adhesive Sealant Cartridge

3M 5200 Marine Adhesive Sealant has earned its reputation as the go-to permanent bonding solution for marine professionals and experienced boat owners across Canada. This one-part polyurethane adhesive sealant chemically reacts with moisture to deliver exceptionally strong, flexible bonds that withstand the punishing marine environment — from the salt spray of the Atlantic coast to the freeze-thaw cycles of the Great Lakes.

Once fully cured, 3M 5200 creates a bond so strong that mechanical removal is typically required for disassembly. This makes it the ideal choice for structural joints and permanent installations where long-term reliability is paramount.

Bonding and Sealing Applications

3M 5200 excels in both structural bonding and permanent sealing applications throughout your vessel. Its versatility across substrates makes it suitable for a wide range of marine projects.

• Fibreglass deck to fibreglass hull joints
• Wood to fibreglass bonding
• Portholes and deck fittings
• Motors on fibreglass transoms
• Under mouldings and trim
• Hull seams above and below the waterline
• Centreboard trunk joints
• Between struts and planking
• Stern joints and deck housing

Substrate Compatibility

3M 5200 provides high-strength bonding to a broad range of marine substrates including gelcoat, fibre-reinforced plastic (FRP), wood species (fir, teak, pine, oak, maple, mahogany), and primed metals. It also bonds to many plastics, though pre-testing is always recommended. For metal substrates, priming with an appropriate metal primer may be necessary to achieve optimal adhesion and long-term durability.

Application and Curing

Apply 3M 5200 using a standard manual caulking gun. Cut the plastic nozzle tip to the desired bead size, puncture the inner seal, and apply to clean, prepared surfaces. The product remains workable with a trowel or spatula for up to four hours after application, giving you ample time to position parts and tool the sealant to the desired appearance.

Tack-free time is 4–12 hours depending on humidity (approximately 12 hours at 50% RH, 4 hours at 90% RH at 73°F). Full cure occurs in 5–7 days at 1/4-inch depth with no shrinkage. Protect joints from direct sunlight and rain until fully cured.

Specifications

• Product Type: One-part polyurethane adhesive sealant
• Cartridge Size: 1/10 gallon (10 fl. oz.)
• Tensile Strength (ASTM D412): 700 psi (4.8 MPa)
• Elongation at Break (ASTM D412): > 700%
• Shore A Hardness (ASTM C661): 68
• Service Temperature Range: -40°F to 190°F (-40°C to 88°C)
• Application Temperature Range: 40°F to 100°F (5°C to 38°C)
• Tack-Free Time (73°F / 50% RH): 12 hours
• Tack-Free Time (73°F / 90% RH): 4 hours
• Rate of Cure (73°F / 50% RH): 1/8 inch (3 mm) per 5 days
• Full Cure Time (at 1/4 inch depth): 5–7 days
• Consistency: Caulkable, non-sag paste
• Solids Content: Approximately 97%
• Density: 11.3 lb/gal (1.3 g/ml)
• VOC Content: 38 g/l
• Percent Volatile: 2.83% by weight
• Viscosity: 100,000–500,000 mPa·s
• Bead Coverage (1/4 inch diameter): 31.6 lineal feet per cartridge
• Bead Coverage (1/8 inch diameter): 126.2 lineal feet per cartridge
• Available Colours: White, Black, Mahogany
• Shelf Life: 24 months from date of shipment (stored below 77°F / 25°C)
• Sandable: Yes

Key Features

• Permanent polyurethane bond — creates structural joints that won't loosen over time, even under constant vibration
• Watertight seal above and below the waterline — protects hull integrity in all conditions
• Flexible cure absorbs stress — prevents joint failure from shock, vibration, and thermal expansion
• Non-shrinking formula — maintains a complete seal without gaps as it cures
• Non-sagging paste consistency — stays in place on vertical and overhead seams without running
• Bonds dissimilar materials — joins wood, fibreglass, gelcoat, metals, and many plastics in a single product
• Extended working time — up to four hours to position parts and tool the sealant before skinning over
• Withstands extreme Canadian temperatures — rated for service from -40°C through summer heat
• One-component moisture cure — no mixing required, simply apply from a standard caulking gun
• Excellent salt water resistance — tensile strength maintained after prolonged submersion
• Sandable after curing — allows for a smooth, finished appearance on visible joints