Centering ring thickness

Can someone point me in the right direction in finding or calculating the adequate centering ring thickness for a certain power and outer diameter? I would like to know for example for non-Level 1 G power 29mm, and say a 5.5" diameter body tube, what thickness (and material) centering ring would be needed? (I am guessing mass of the rocket would also come into play, so that'd be 3.3 lbs or less).

If no one can answer that, maybe I can get there by asking this question: for the Estes Pro-Series II kits (F & G power), what is the centering ring thickness for the Mega Der Red Max? Is it cardboard? I know the Red Max is 4", but I'm trying to start somewhere, with the goal being to save centering ring weight.

IIRC, centering rings for my PSII Nike Smoke were 1/8" ply.

I can't remember where but someone did examine the question of CR design and found that for the most part we all use CRs that are "overbuilt" in both thickness and type of material. I'll have to try to dig up that study.

I have done G motors with cardboard . For my builds G-j it's has been 1/4 ply but it may be over kill till you get to J . L- up it would be 1/2

Thank you Tim. You reminded me of something I had read about a year ago, maybe you were thinking of this: https://www.apogeerockets.com/downloads/newsletter126.pdf

Chris, what kind of cardboard?

I've used 1/16" non-corrugated cardboard for centering rings (24mm mounts) in bt60. if you're using ttw fins and not using the motor mount as an anchor point, I would suggest foam-core(3/16"). for open rocket use Depron as a material, you'll be close enough. probably want to give foam core a coat of wood glue to; a)provide some heat protection(ejection & backblast) and b) seal it for painting. had I used foam-core in my current build, I could have saved about 20g .
Rex

455 Buick said:

Thank you Tim. You reminded me of something I had read about a year ago, maybe you were thinking of this: https://www.apogeerockets.com/downloads/newsletter126.pdf

Chris, what kind of cardboard?

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Yep, that's it. Thanks for the link.

Thanks Rex.

dixontj93060 said:

Yep, that's it. Thanks for the link.

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That's funny, I should be thanking you for reminding me!

455 , just like rex non corrugated card board , you can get it at hobby lobby .

chris m said:

455 , just like rex non corrugated card board , you can get it at hobby lobby .

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They (HL) have packs of matboard (thick cardboard) for very cheap. The pack I have at hand is 35 pieces of 5x7 for $3.99. I've built several rockets using the stock centering rings and yellow glue, with 24mm engine tubes and composite motors. One of my favorites was a stock Fat Boy with a 24mm mount that flew on Econojet F motors. Loud, smokey, fun flights - the flame was several times the length of the rocket.