53 replies to this topic

[StephenSLR]

Are you talking bending moment, sheer stress or brittleness?

the first two moreso than brittleness.

The metal will would be more malleable than the fibre so could help assist it from deforming beyond its elastic limit.

There's no better way than to make the stuff yourself and do a few tests to find the strengths and weaknesses. It could probably be done with computer modelling - finite element analysis, not for the weak hearted.

Many products have been invented through persistence so go for it, also many things were invented by accident.

i.e. Kevlar, (I think)

I recall a story of a woman who had been in charge of the extruding machine and I think she let the molten liquid harden overnight in the machine, then started it up the next morning it heated twice, hardened and stuffed up the machine.

They sacked her for ruing the machine, then when the tested the material found it to be very strong, they re-hired her and gave her a share in the company to develop the material.

2. post-it notes.

A guy working for 3M spent so long inventing a super glue and it turned out to be so piss-weak the bosses were on the verge of sacking him. Someone came up with a use for it - put it on paper squares to stick up and remind you of things.

I don't know if these are urban myths but good stories nonetheless.

s

[Statler]

It's no urban myth......alloy cages aren't 'wanky'!

[Heath]

I think the brittleness of carbon fibre would limit its acceptance, but if it was so over-engineered that it would never be close to reaching its point of fracture (I'm assuming it doesn't have much of an elastic range but that's merely an assumption, never seen it tested), then it may be a different story. And still potentially quite lightweight

Roll cages aren't just about stopping occupants from getting hurt - they're about stiffening the shell up! And for that, carbon fibre is good shit. I don't know what the best ways to attach a carbon fibre structure to a steel structure is. I've seen a fair bit of high quality shit that has alloy and carbon fibre nicely moulded together so it's not something that hasn't been done, but applying it to chassis mods etc may not be as simple or effective as what I've seen with other examples.