3450W of Solar Power on Our Off-Grid Catamaran
After three failed welders and two years of work, the new solar arch is finally up. 3,450 watts and the batteries are full by noon.
Four welders. Two years. Hundreds of hand-cut stainless pieces. And by mid-afternoon most days, 64kWh of batteries are sitting at 100% before noon. The solar arch that took longer than almost any other project on this boat is finally up, and it's the one we both agree turned out better than expected.
Three welders flaked out before the fourth one finally committed to the project. In the gap between each attempt, the design work, measuring, and fabrication kept moving — because waiting for a welder isn't a reason to stop making progress on everything a welder doesn't need to touch.
Four welders, two years, and hundreds of hand-cut stainless pieces later, the solar arch is finally up — and it's already fully charging the battery bank by noon.
What Happened
The old solar arch came off first, clearing the way for a larger structure built to hold four 570-watt bifacial panels plus two additional panels mounted on the coach roof — 3,450 watts total. The new arch had to be measured and fitted by hand: finding centerline, calculating offset from the transom, and setting leg height above the factory reinforcement line that supports the davits and dinghy.
Nothing on the boat matched side to side, which meant the leg placement designed for one side didn't translate directly to the other. Leg positions had to be reworked to land on usable structural points in the roof rather than forcing new holes where the fiberglass couldn't support them.
Cutting stainless became the bulk of the work — fifteen pieces for the cross braces alone, each requiring 45-degree angle cuts and radiused holes sized to match the tubing. Old blue tape covering the stainless turned out to be brutal to remove after sitting outside, requiring mineral spirits and a lot of patience. Two of the original safety rails from the sugar scoops were saved, polished, and reused rather than replaced — stainless in decent shape with no reason to throw it away.
Once the fabrication was done and the welder came through, wiring the panels, running cable, and mounting each panel by hand finished the project. A cockpit shower and foot wash were added into the structure along the way.
Why It Matters
By building the arch ourselves instead of handing it entirely to a welder kept the project moving and kept costs down. Measuring, cutting, and fitting every piece meant the welder's time was spent welding, not designing or problem-solving on-site. That division of labor is a big part of why the final cost stayed reasonable despite three failed tradesman relationships along the way.
3,450 watts fully charges the battery bank by midday, even with two panels not yet wired in. That's a meaningful step toward running the boat without shore power or a generator — the kind of self-sufficiency that makes extended cruising away from marinas realistic.
Reusing the safety rails instead of replacing them was a small but deliberate choice. They were structurally sound stainless in good condition. Replacing functional hardware for the sake of a fresh look would have added cost and waste without adding value.
Persistence through partner failures mattered as much as the fabrication itself. Three welders backing out over two years could have stalled the project indefinitely. Continuing to prep, measure, and cut in the meantime meant the fourth welder walked into a project that was ready to move quickly.
Tools / Products Used
Bifacial Solar Panels Jinko Tiger Neo N-type 72HL4-(V) — 575W (no relationship)
Four panels configured in two series pairs mounted on the new stainless arch, generating the bulk of the system's 3,450 watts.
Vevor Pipe and Tubing Sander (no relationship)
Direct Link - Used to sand the welded joints smooth to 1200 grit in preparation for polishing
Hercules (Harbor Freight) Metal Conditioning Tool (no relationship)
Direct Link - Used to polish stainless plate and joints
Hercules (Harbor Freithg) Portable Band Saw and Bench Top Stand (no relationship)
Saw Link - Stand Link - Used to make straignt and angle tubing cuts as well as cutting plate in it's vertical mode.
No affiliate links or partner relationships to disclose in this episode.
Related Episodes
This project connects to the broader power system work covered in the electrical rebuild series, including the power wall build in EP62.
What Comes Next
Two coach roof panels are mounted but not yet wired in — the wiring path still needs to be worked out. Once connected, total solar capacity goes fully online. With the arch complete and the battery bank charging to full most days before noon, the boat is closing in on genuine off-grid capability heading into the next phase of the refit.
