Andrew_ASC
UTC SEDS 2017 3rd/ SEDS 2018 1st
- Joined
- Sep 22, 2017
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Yeah, I'm gonna backtrack on the picture wire being O.K. I just remembered that black powder residue is corrosive to bare metal. That's why you see gun enthusiasts seemingly obsessively cleaning their firearms: it's to keep the internal parts from pitting and corroding.
Also picture wire will break after repeated bending, like a paper clip that is bent back and forth. Use a high tensile clear coated steel cable instead.
Theoretically that corrosive will cause surface flaws and affect life cycle of component from machine design knowledge as a surface defect slight crack propagation and the surface finish itself. And your other steel wire will have a higher life cycle before failure but it will still fatigue fail. I've done textbook integral problems in material science for some applications such as heavy aircraft spars they say several million cycles. Other applications like this rocketry shock cord stuff I just won't trust it. It bends and could twist too. You may have not seen torsional failures. I have seen a inch diameter steel rod A-36 structural just torsion fail by twisting in a lab machine. It took very few rotations to happen under harsh loading. It looked like a candy cane and appearance changes then it starts necking then a loud kink noise as it fails. Though I'm just an undergrad mech. But yes they still show the paper clip fatigue failure in class to engineer students.
Not trying to bash anybody's feelings. Try to use better fireproofing materials, higher temp epoxies,
multiple mount points, or shielding tactics around non metal cords nylon, Kelvar, etc. okay with metal D links or even bolts. But a shock cord... I pause.