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0 pointszevets12y ago0 comments

Looking at the specs page, their claimed yield stress is 20% higher than aluminum compared to a factor of ~4x for traditional CF composites.

Also concerns about the fiber content may be misguided. The hard part of CF compoisites is the the layup process, which is what a 3D printer would do. The part can then be vacuum bagged to pull out the resin, as in traditional CF manufacturing techniques.

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MechSkep12y ago

Where did you get that yield stress number? Is it from that graph with Aluminum and the plastics?

Because that graph shows modulus(stiffness), not strength. Which is pretty hinky when placed next to the statements about strength. Looks to be a bit misleading.

On top of that "stronger" has no meaning when it comes to composites. There are about 9 different failure modes, and you can't just choose one and report the "strength". I'm guessing they're talking about axial tension numbers (because I'm cynical) where their material would perform the best. Even then, their yield strength is about 200MPa (based on the "5x stronger than ABS" statement) whereas aluminum's yield strength tops out around 600MPa.

zevetsOP12y ago

Good catch on them showing E vs strain instead of stress/strain. Very misleading, as it clearly got me!

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