mathew said...Imax said..
Ian , as an engineer and a heavy 120kg boom bending bastard I do understand metallurgy or carbon mallubilaty. As stated earlier longer and shorter boom use the same strength bar stock , so longer booms will be weaker than short ones all things being equal. The question was will a smige longer effect the strength , I think not as long as there is enough overlap as to not kink the structure , although there will be a slight more flex due to the length ,
Carbon doesn't have the notion of malleability - that term is largely limited to ductile materials such as metals... ie: specifically, it is the ability to change shape without fracture.... Carbon fibre cannot change shape at all, as it is an extruded/drawn fibre.
Back to the original question - longer booms are usually heavier (so all things aren't equal)... I'd third the statement that no calculations are actually done.
IMax notion of 'carbon' malliability refers to the composition of carbon, resin and its componant design maliability. Carbon fibre does bend without breakage, hence why it can be supplied as a cloth and transported on a roll, and why it can be used to make highly flexible components like masts. Carbon fibre filament(the smallest isolated strand of carbon) do stretch. High Modulus carbon stretches less than Low Modulus carbon..and in between those there are Medium and Intermediate Modulus.
To make a carbon fibre componant lighter and stiffer, you need to use High Modulus carbon. You achieve the required stiffness with less weight. To achieve the same stiffness with lower modulus carbon you need to use more carbon. The structure with therefore be heavier, yet stronger.
Without knowing the composition(pieces of string) and the properties of each element of composition(The sum of How Long is a chinaman) of the boom in question, it is impossible to provide an estimation on the durability of pre-posed tail piece retrofit.
I'd do it.
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