CNC Machined Stainless Steel 316 Marine Deck Fitting with Passivated Surface for Boats and Vessels

Deck fittings are essential components that endure significant stress and environmental exposure on any vessel. Cleats, chocks, bollards, and stanchion bases withstand constant loads, salt spray, and UV degradation while ensuring vessel security.

Marine deck fittings face extreme conditions—a 40ft sailboat in 30-knot gusts can exert 2-3 tons of load on a single mooring cleat. This cyclic loading, combined with constant salt spray and UV exposure, demands robust materials and precise manufacturing.

Stainless Steel 316 is the industry standard due to its molybdenum content (2-3%), which provides superior pitting resistance in chloride environments compared to 304 stainless steel. Our fittings are machined from solid 316 bar stock, ensuring dimensional consistency and material integrity that castings cannot guarantee.

• Solid 316 Construction: Machined from certified SS 316 bar stock—no porosity, no casting defects, full material traceability
• Mounting Surface Flatness: <0.1mm on base surfaces for proper sealant bedding and uniform load distribution
• Load Capacity: Designed to exceed ABYC working load requirements by 2x minimum
• Edge Treatment: All edges radiused or chamfered—no sharp edges to chafe dock lines or damage deck surfaces
• Surface Treatment: Passivated per ASTM A967 for maximum pitting resistance, optional mirror polish for premium applications
• Thread Quality: Tapped mounting holes with 6H tolerance—no cross-threads, no galling issues with 316 fasteners

• Mooring Cleats: Heavy-duty deck cleats for permanent mooring applications on sailboats and powerboats
• Bow Chocks: Roller chocks and open chocks for anchor line guidance on vessels 20-80ft
• Stanchion Bases: Mounting bases for pulpit and lifeline stanchions with precision socket features
• Hawse Pipes: Deck-level fairleads for anchor chain and heavy rope routing
• Deck Plates: Flush deck plates and access covers with O-ring sealing surfaces
• Rod Holders: Angled and vertical rod holders for sport fishing vessels

• No Castings, Ever: All fittings machined from solid bar stock—consistent grain structure, no hidden porosity, predictable mechanical properties
• Marine-Specific Surface Treatment: Passivation process tuned for marine chloride resistance—verified salt spray performance beyond standard compliance
• Line-Friendly Edges: All rope-contact surfaces radiused to prevent damage to expensive dock lines
• Thread Compatibility: Tapped threads sized to minimize galling risk with proper lubricant for 316 fasteners
• Volume Consistency: Maintained tolerances and finishes across production runs for outfitting multiple vessels with identical hardware

1. Design Review: Verification of fitting design for wall thickness adequacy, fastener pull-through strength, and rope contact geometry
2. Material Preparation: SS 316 round or hex bar, oversized for cleanup with chemical composition verified per ASTM A240
3. CNC Machining: 4-axis milling for profile and features, simultaneous turning for round bodies with tight chip control
4. Deburring & Edge Treatment: Vibratory finish for overall deburring, manual edge radiusing on rope-contact surfaces
5. Passivation: ASTM A967 nitric acid passivation with post-passivation rinse in DI water
6. Inspection & Packaging: Dimensional check, surface finish verification, thread gauging, individually wrapped in VCI film

A: For most recreational boats under 40ft, cast fittings are adequate. For commercial vessels, racing boats, or safety-critical applications where fitting failure creates hazards, machined fittings are essential. The price difference reflects the superior material integrity.

A: If you own the design rights, yes. We do not reproduce proprietary designs without authorization. However, we can reverse engineer from samples to match discontinued brand footprints.

A: Satin brush finish is recommended for most applications. Mirror polish offers aesthetic appeal but shows scratches from line contact. Passivation is essential for all saltwater service regardless of finish level.

A: Yes. Duplex 2205 provides approximately 2x the yield strength of 316 with excellent pitting resistance, ideal for offshore towing bollards and commercial fishing equipment.

A: We can produce 1000+ fittings monthly with single setup and SPC monitoring on critical dimensions, ensuring consistency with volume pricing.

A: Yes. We can machine fittings with matching backing plates as sets, including alignment features for proper installation—common for high-load stanchion bases.