The Cherbourg Incident
When a broken mainsail track gate threatened to derail a racing season. How scanning and printing a custom gate cut local wait times from 3 weeks to 8 hours.
It was mid-season in northern France. S/V Osprey was docked in Cherbourg, preparing for the offshore delivery run across the English Channel, when the mainsail track gate fractured. The gate is a small but critical piece of anodized aluminum that sits at the base of the mast, keeping the mainsail sliders secure inside the mast track when the sail is reefed or lowered.
Without it, hoisting the sail was impossible; the sliders would pull out of the mast track under load. The mast manufacturer was based in southern Europe, and they quoted a three-week delivery window for the replacement casting, effectively ending our summer sailing campaign.
High-Accuracy 3D Scanning
We refused to wait. We removed the shattered fragments of the cast gate, brought them into the cabin, and set up our high-resolution handheld structured-light scanner. Within fifteen minutes, we had captured a clean, 3D point cloud of the broken parts.
We imported the scan data into CAD, aligned the fractured surfaces, and reinforced the structural neck where the casting had sheared. The original part was thin-walled aluminum; we increased the thickness by 3mm, optimizing the design for printing.
8 Hours from Scan to Sail
The file was sliced for printing in PA-CF (Carbon-Fiber Nylon) to ensure maximum stiffness and resistance to deformation under sail load. We ran the print with solid infill and active chamber heating.
Eight hours after the initial failure, the printer completed the job. The part was cleaned, test-fitted on the mast track, and bolted in place. The fit was exact.
We sailed that afternoon, completing the English Channel crossing in 25-knot winds. The printed gate remained in service for the rest of the season, performing flawlessly under active racing loads.