Designing a marine linear actuator for boat applications requires careful consideration of durability, power, water resistance, and corrosion resistance. Below is a step-by-step guide to making a boat linear actuator for applications like trim tabs, hatch lifts, or throttle control.
• Load Capacity: Determine the force needed (e.g., 50 lbs, 100 lbs, 500 lbs).
• Stroke Length: How far the actuator needs to extend (e.g., 6", 12", 24").
• Speed: Desired extension/retraction speed (e.g., 1 inch per second).
• Environment: Saltwater/freshwater exposure, submersion risk.
• Power Supply: 12V or 24V DC (common for boats).
• Uses a DC motor + lead screw/ball screw.
• Example: 12V 200-lb thrust, 6" stroke (available pre-built).
Hydraulic/Pneumatic:
• More powerful but complex (requires pump, hoses, seals).
• Manual Backup: Optional for critical systems.
Brushed DC Motor: Simple, cost-effective.
Brushless DC Motor: More efficient, longer lifespan.
Gear Reduction: Increases torque if needed.
Housing: Stainless steel (316 grade) or marine-grade aluminum.
Shaft: Stainless steel or nickel-plated steel.
Seals: IP67/IP68-rated for waterproofing.
Rod End Bearings: Self-lubricating, sealed.
Limit Switches: Prevent over-extension.
Manual Override: Optional for emergencies.
Wireless/Remote Control: For convenience (e.g., Bluetooth, RF).
Motor & Screw Assembly:
• Attach a lead screw or ball screw to the motor shaft.
• Use anti-backlash nuts for precision.
Housing Construction:
• Seal the motor and screw inside a waterproof tube.
• Use O-rings and marine grease.
Mounting Brackets:
• Weld or bolt stainless steel brackets for boat attachment.
Wiring & Waterproofing:
• Use marine-grade connectors (e.g., Deutsch connectors).
• Seal with heat shrink tubing or waterproof junction boxes.
Purchase a heavy-duty linear actuator (e.g., from PJM, Thomson).
Add marine-grade coatings (e.g., zinc plating, epoxy paint).
Replace fasteners with stainless steel.
Freshwater Test: Submerge in water to check for leaks.
Salt Spray Test: Simulate ocean conditions.
Load Test: Verify performance under max load.
Mounting: Secure to a rigid part of the boat (e.g., transom for trim tabs).
Wiring: Connect to the boat’s battery via a fuse/switch.
Control: Use a waterproof switch or wireless remote.
Rinse with freshwater after saltwater use.
Inspect seals annually.
Lubricate with marine grease.
• Buy: Faster, guaranteed waterproofing (e.g., Seastar Solutions, Lenco, Livorsi).
• Build: Customizable, cost-effective for DIYers.
Would you like recommendations for specific marine grade actuators based on your boat’s needs? Contact with PJM engineer team now.
