Talk to someone who went on previous trips on the Titan submersible and they’re likely to mention a technology glitch. The propulsion system failed or the communications with people on the surface cut out. They are also likely to mention Stockton Rush. He’s the OceanGate Expeditions CEO who died this week on the sub. Rush has been described as both a meticulous planner and an overconfident pioneer. In the wake of the Titan’s fatal implosion Sunday near the Titanic shipwreck, some passengers from previous expeditions described concerning experiences that foreshadowed the tragedy. Still, others felt they were in “good hands” deep below the ocean’s surface.

  • artillect@kbin.social
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    2 years ago

    Huh, I didn’t even know carbon fiber had a shelf life, I figured it’d be pretty stable over time.

    Here’s the reason why, in case anyone’s curious (I know I was):

    Fabrics and prepregs also degrade gradually over time. In composite laminates it is not the fiberglass, carbon fiber or Kevlar fibers themselves that initially degrade. It is the sizing or fiber primer however that degrades over time. Sizings are placed upon the fibers to make them more compatible with a given resin system during cure. As time goes on fiber sizings diminish, weakening the future link between the fabric and the resin, thus yielding a possibly weaker composite laminate.

    The exact storage life of most sized fabrics is not always listed on a technical data sheet. Often one may need to research further into a manufacturer’s technical manuals for an expected shelf life of a fabric sizing. Fiber sizing life can range from a year to beyond five when stored under favorable conditions. For prepreg materials a general shelf life is first a year. After a year or after initial expiration some fabrics and prepregs may be re-tested for performance against its original stated performance specifications and bonding characteristics. In the case of a DIY project possibly using expired fabrics it is important to test a laminated section of the expired fabric to ensure its quality is up to par for its intended use.

    • HubertManne@kbin.social
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      2 years ago

      wait wait wait. Does that mean carbon fiber bike frames are likely to bust in a crash after a few years??!!!

        • Zana@kbin.social
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          2 years ago

          If I buy this now I don’t want to rule out the possibility I may do that one day.

        • HubertManne@kbin.social
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          2 years ago

          so the storage life assumes being under 1500 ft of water??? (edited. sorry guys was playing with settings and put the one that auto adds ats. going to take that back out.)

      • floofloof@lemmy.ca
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        2 years ago

        They are known to be more fragile than frames and forks made of other materials. They need to be checked regularly for tiny fractures that could lead to a sudden collapse, and if they get hit from the side they can be more easily damaged since the tubes are designed for longitudinal strength. I’m sticking to aluminium.

        • cassetti@kbin.social
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          2 years ago

          Well hot damn, glad I didn’t get a CF hybrid bike. I was thinking about a CF fork upgrade for my bike, but I think I’ll just burn the extra calories instead hahaha

        • HubertManne@kbin.social
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          2 years ago

          ty sir. that makes it not so bad. still I have had some bikes for decades. I was never able to afford carbon fiber anyway but now I think I will avoid even if it became cheap. sorta wish the carboard bike had become a thing though.

      • timdesuyo@kbin.social
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        2 years ago

        They are likely to bust in a crash, period. But without any crashes, yes, they degrade over years of sunlight and exposure to the elements, and that is something that you should always calculate in your risk assessment of the bike that you ride.