The main one is the resin that is bring used, that will have a shelf life like paint or glue as the solvent will evaporate. The second one is fibre primers that are used to help the resin integrate with the Carbon Fibers can degrade and cause improper bonding between the fibres and layers. For fabrics this is normally over a year but for prepregs (where the resin already in the fibres but not set) is generally a year and will need testing for a longer shelf life.

Another issue is the storage you want a cool dry environment and covered to avoid contamination from other rolls/prepregs. Additionally the other thing that worries me is although salt water is not an issue to the fibres and resins themselves when you add metal to them the salt acts as an electrolyte and will cause galvanic corrosion "rusting" away the fasteners and causing damage to the fibres in that area.

Not to mention Carbon Fiber is best for coaxial (along the length of the tube) tension not hoop (around the tube) compressive forces. And differences in the layup and curing process can impact the viability of the final part which is why lots of places will weigh the resin and have a procedure to soak the fibres and lay them up as well as sensors to keep the pressure and temperature with a margin for curing, to keep the variability between the parts minimal.

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