Most consumer 3D printing happens in PLA, and PLA has no business on a boat. It softens in a hot cockpit locker, creeps under sustained load, and UV breaks it down. When a printed boat part fails and sours someone on the whole idea, PLA is usually the reason.
What we actually use: ASA for anything that lives in the sun, because it's UV-stable and handles salt spray without chalking. PETG-CF where stiffness and load matter — cleat bases, brackets under rigging load, fittings that get winched against. TPU for gaskets, seals, and anything that has to flex a thousand times without cracking.
Material selection is the difference between a part that lasts a season and one that outlives the boat. It's the first question we answer in every quote, and it's why we publish per-gram pricing by material instead of pretending one plastic fits all.