: Sam,

: Many thanks for your reply.
: Actually I am trying to check if glass fiber (which is stored for a
: long-time) could be used for FRP pressure pipe or not?

: Reza

Reza,

Since fabricating pressure pipe exposes you to more concerns than we face with DIY kayak projects, you should consider some quantitative tests before fabricating pipe. For the purposes of wood strip kayaks, the glass isn't a big issue, but the comments in this thread about glass being inert or immune to degradation simply aren't accurate. It's an okay assumption for pretty kayaks where we mostly want clear wet-out, but the effects of glass degradation on mechanical properties of composites is well documented and understood.

Feel free to contact me offline for further discussion regarding your pressure pipe (sam@anametinc.com).

Sam