Installing the Propulsion System on Aluminum Catamaran Delos 2.0

Propulsion System Installation

• 🛠️ The propulsion system for Delos 2.0, including the propeller and Sigma drive, has finally arrived and installation is beginning.
• 💡 This system is crucial for efficiency and performance, with catamarans featuring two engines for enhanced maneuverability.
• 🎯 Key considerations include prop size, pitch, placement, and precise shaft alignment to prevent vibration and wear.

Components and Engineering

• 🌊 A Cutlass bearing within a fiberglass tube is installed, acting as a water-lubricated bearing for the 35mm prop shaft, ensuring steady rotation.
• ⚙️ The Brunton's EcoStar H6 propeller is a 20-inch diameter, 35mm shaft prop tuned for electric/hybrid drives, featuring feathering blades for sailing and optimal pitch for motoring.
• 🔗 The Brunton Sigma drive serves as the coupling between the transmission's output and the propeller shaft, handling vibrations and allowing for up to three degrees of misalignment.

Precision Alignment and Measurement

• 📏 Shaft alignment is critical; minor misalignments can cause premature wear and vibration. Feeler gauges are used to measure and adjust clearances between the clutch and gearbox flange.
• 📐 Accurate measurement of the prop shaft length is essential, accounting for insertion depth into the Sigma drive (40-60mm) and space for a line cutter.
• ⚠️ Ensuring adequate clearance between propeller tips and the hull is necessary, especially for the auto-feathering prop whose blades can rotate 360 degrees.

Installation Process and Challenges

• 🔩 Temporary nylon bolts are used to position the stern tube, ensuring alignment before pouring chockfast to secure it.
• 🚧 Aluminum tubes are created to form a tunnel for the chockfast, allowing access to screws for potential Cutlass bearing replacement.
• 🩹 A minor mistake in drilling an access hole for a screw was corrected by filling the hole with aluminum and re-drilling, highlighting the importance of fixing errors.

Securing the Stern Tube

• ✅ Steve, a consultant, reviewed the work and confirmed the alignment was good, giving the go-ahead to chockfast the stern tube into place.
• 💧 The chockfast mixture, calculated using AI to be 1.28 liters, was prepared and poured into the stern tube, with dams in place to prevent leaks.
• ⏳ The mixture needs time to cure, with the process expected to take about an hour to kick off and be fully set by the next day.
• 🚀 This marks a major milestone, with half of the propulsion system installed, bringing Delos 2.0 one step closer to sailing.