internal fillets keep the fins from pulling thru the wall
I have had epoxy only external fillets crack, so I started reinforcing
I have seen many rockets lose surface mount fins and the rocket self destructed
Yes it adds some strength, but not near as much as adding reinforcement fibers or cloth
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The physical properties of composites are fiber dominant. This means that when the resin and fiber are combined, their performance remains most like the individual fiber properties. Test data shows that the fibrous reinforcement is the component carrying the majority of the load. For this reason, fabric selection is critical when designing composite structures.
https://www.fibreglast.com/product/about-reinforcements
Its a little more complicated I think; Fillets add huge strength if done properly...
Internal fillets add strength, keep fins from pulling out and add damping to twisting moments.
Fillets can crack if too hard of epoxy is used for example. Too soft is not good either.
Surface mount fins are the hardest to keep on, that be true!
I don't like to T2T reinforce because it destroys the rocket diameter... Poop slow and low.
Question #97 - Although not a laminating expert, it seems that most of the strength gained by adding a T2T reinforcement cloth material would be along the direction of the fabric. For example Kevlar is only strong in one direction... How does this keep the fins from bending and flexing in all three axis modes?
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