75 mm minimum diameter "L" motor design

[Paul Whalen]

Hi

How do you decide between materails for a 75 mm mimimum diameter rocket on an "L" motor .

Fiberglass , fiberglass profusion , and or carbon fibre which is sufficent to handle the strain yet the easiest on your pockety book without taking chances with safety?

Thanks
Paul

 

[dixontj93060]

Safety isn't so much the issue as, done right, any of those airframe materials will work (not saying to ignore compression, lateral forces, but these usually "the short straw" in MD flight failures). More an issue with material selection is performance. Big difference in weight between what you have listed and. depending on manufacturer, wall thickness/OD driving drag.

 

[3stoogesrocketry]

The answer to your question depends on what L motor your flying . Is it mild like a L850 or wild like a L2375 ? Plain cardboard will hold a mild L / M motor , while a wild small 54mm L might shread the same design.

Eric

 

[Paul Whalen]

Hi

An L 1115 Classic will bring me to 1076 mph, not overly that fast . Wieght is not a concern due to the optimal mass puts the rocket at approx 8 lbs empty and it is currently 3 lbs ( G-10)without the AV bay added . Infact if it was a lighter material I would end up having to add more weight .

So it sounds if wieght is not a concern and the cheapest product (regular fibre glass) is the best choice?

Thanks
Paul