The Spartite Mast Chock & Seal Solution
Spartite is transforming how boaters approach mast support and partner sealing. This innovative two-part polyurethane polymer system offers a modern alternative to traditional wooden or rubber mast wedges, providing a custom-molded fit for your boat's deck collar.
How Spartite Works
Spartite 2000 is poured directly into the cavity between the mast and partners while the rig is stepped and properly tuned. After applying a mandatory mold release agent (petroleum jelly) to the deck collar and building a bottom foam dam, the liquid polymer is poured in place. It cures into a flexible, custom-fit, solid polymer chock that eliminates localized pressure points and replaces outdated wedge systems.Key Technical Specifications & Parameters
- Kit Sizes: Kit #1 (51 cu. in. / 835 cm³) for boats up to 40'; Kit #2 (102 cu. in. / 1,670 cm³) for boats 36'–60'.
- Physical Properties: Cures to a Shore 60D hardness with minimal linear shrinkage (~0.001 in/in).
- Pour Depth: Requires a minimum pour depth of 2 inches (50 mm) at the partners, extending a 1/4-inch lip over the deck ring.
- Cure Times: Pot life of ~15 minutes at 77°F (25°C); initial set in 2 hours; full structural cure in 24–48 hours depending on ambient temperature.
Benefits of the Spartite Pourable Chock System
- Load Distribution: Creates a 100% continuous, 360-degree molded bearing surface that distributes mast loads evenly across the partner ring.
- Removable Design: When installed with proper release agent, the cured chock remains bonded to the mast while releasing cleanly from the deck collar for easy rig removal.
- Vibration Dampening: Reduces rig slap and dampens impact loads transferred to the deck structure.
- Long-Term Sealing: Fills the void down to millimeter tolerances; finished with a perimeter bead of marine sealant to ensure complete watertight integrity.
Frequently Asked Questions
What is a Spartite mast seal and chock system?
Spartite 2000 is a pourable, two-part polyurethane polymer system used to chock and seal a boat's mast at the deck partners. Poured while the spar is stepped, it forms a custom, one-piece molded ring that replaces traditional wooden or rubber mast wedges.
How does Spartite compare with traditional mast wedges?
Unlike wooden or rubber wedges that create isolated point-loads and shift over time, Spartite cures to exact partner dimensions. It creates a continuous 360-degree load-bearing chock that prevents mast movement at the deck while dampening rig vibration.
Can a DIY boater install Spartite 2000?
Yes, DIY boaters can install pre-measured Spartite 2000 kits. Success requires following strict prep steps: tuning the rig beforehand, building an airtight bottom dam, and applying petroleum jelly to the deck collar interior to prevent permanent bonding (die-locking) during unstepping.
Does Spartite require additional sealant after curing?
Yes. While Spartite fills the cavity between the mast and partners, manufacturer standards recommend running a bead of flexible marine sealant (or UV-resistant sealant) around the top seam between the polymer edge and deck ring to ensure complete watertightness over time.