On 09/07/2018 07:08, Ian Smith wrote:

On Sun, 08 Jul 2018 14:29:15 +0100, Peter Parry wrote:
On Sat, 7 Jul 2018 12:38:15 -0700 (PDT), wrote:

Cue a new rear mech and a spoke BUT a LBS insisted that the carbon
frame is also bent and they won't put it in a jig to straighten it.
How can a Carbon stay bend?

Stress any material beyond its elastic limit (yield strength) and it
will deform and stay deformed. You can't bend it straight again..

Really.

What do you think the yield stress of, say, a china plate is?
Do you think you can bend that so it stays bent?

He didn't say "bent". He said "deformed". A stressed china plate will
certainly be that.

And any material bent plastically stays bent forever. Hmm.

Maybe.

PS: You can learn something every day. "Plastically" was a new one on
me, but there are 636,000 instances of it on UK Google. Thanks for that.