Sailing SV Delos · video

What this video covers

Fabricating the longeron and forward crossbeam for the 5083 aluminum expeditionary catamaran requires precise alignment to manage the structural loads of the forestay and anchor system.1:59 The longeron, a hollow structural member extending from the bridge deck, incorporates three chain plates for the jib, self-tacking jib, and downwind sails, while housing the anchor chain internally.1:11 During assembly, the crew encountered a 40-millimeter misalignment caused by incorrectly marked side plates, which they resolved by recalibrating measurements and using temporary bracing and a come-along to correct a twist.6:14 To prevent aluminum warping during welding, the team alternated sides and spaced out welds to distribute heat evenly.8:03 Final positioning involved using a laser level to ensure the structure was centered relative to the hull and bridge deck before tack welding.18:30 The project concluded with the installation of 32-millimeter thick chain plates and a Mantis Marine M2 anchor mount.22:02 Meticulous measurement and temporary structural bracing are essential for maintaining alignment when welding large, complex aluminum components.

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