A heretical statement, but I was wondering when CF ISN'T the answer ? If I have a structural design which is STIFFNESS driven, like a wing or telescope, rather than strength driven, is CF "better".

I've been studying the concept of specific modulus, or stiffness-to-weight ratio and ended up in a confusion of different design approaches related to the telescope project I mentioned last week.

Steve

carbon like any other material has its structural pluses and negatives.

you merely select an appropriate material for the job.

When you take into account cost and sometimes ease of manufacture, it is clear that carbon may not be the best choice overall, even if it is structurally superior to the alternatives.

Yes, well that's obvious, but I'm asking more from the structural engineering perspective.

Steve

not that i'm any good at engineering or design for that matter! but i'd say that CF is not always the answer, stiffness i would say naturally comes from mass,  if you take for example engineered timber joist's,  fine if you use them for what they were designed for but not laid flat on their side. a tree for example is still stiff laid flat.

i guess coremat sandwiched between cf would produce effectively the same as engineered timber joist's right?

times like these i wish i was intelligent lol