Back in the day, circa 1995, a Tripoli rocketeer, named Bruce Lee, developed a simplified method to manually calculate Center of Pressure.

His 10-year old son was able to do the computations with ease.

Dave F.

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Smart 10-year old!

I still use the cardboard cut-out method.

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Don
NAR 53455
"Carpe Diem"

DEFINITELY, a LOT SMARTER than what today's "Schools" are turning out !

Dave F.

Nothing wrong with that, as it is very "conservative" about CP location.

It gives a "safe" CP location ( FORWARD of its ACTUAL location ) . . .

The "downside" to the Cardboard Cutout method is that it "calls for" extra Nose Weight, which reduces performance and creates an "overstable" situation.

Dave F.

Does this Bruce Lee also have a sister named Ugh ?

I don't ever bother with CP calculation. I just fly it. If it flies ok, the CP/CG relationship is ok too.

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When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.

That gave me a "flashback" to my youth . . . Home-made fireworks, labelled with a felt-tip marker "Light Fuse & Run Like Hell" . . . LOL !

Dave F.

Their relationship may seem ok, but they still need a chaperone.

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I love sanding.

this is what OpenRocket is for. or RockSim or RASAero 2

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"Old Rocketeer's don't die; they just go OOP".....unless you 3D print them.

Chaperone nuthin'
We dun't neeed no steeenkingg chaperone!

__________________
When in doubt, WHACK the GAS and DITCH the brake !!!

Yes, there is such a thing as NORMAL, if you have to ask what is "NORMAL" , you probably aren't !
Failure may not be an OPTION, but it is ALWAYS a POSSIBILITY.