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Joshua Smith

kernelsmith
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If your margin of stability is 1.14, then you don't need nose weight. But I would suggest a lower thrust motor. 36G might tear up a cardboard rocket. How about the H128W? Little longer burn, lower thrust, less G's pulled.
I think technically, the 1.14 caliber stability was from @Zeta's modeling with some amount of nose weight so it's hard to say. @Spacey you may want to either model it yourself, or weigh your rocket and find the Cg and ask Zeta to override the weight and Cg in the model, or ask Zeta to send you the current model so u can override those values.

Also, @Zeta, not that it will change much but @Spacey's fins are balsa papered with cardstock vs plywood. However, modeling that might not be too simple in Open Rocket? I have never modeled papered fins, even tho I have papered some of my own fins
 

Joshua Smith

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I ended up using the self adhesive derby weights && attached them to the back of my sled.
Ahhh, that kind of derby weight. I was totally blanking on what you meant earlier. Just be sure they won't vibrate off of the sled.
 

Joshua Smith

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More pictures.. Primed & waiting to be painted!!
For your nose sled, did you make the rings yourself? If so, may I ask how? Was it like a classic jig saw situation, or a rotary drill circle cutter thingy etc?
 

Cape Byron

The BAR formerly known as Skippy-2
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I thought the same thing. What is a derby weight. I was thinking fishing.
It's weird (or I am). I saw 'Derby weight' and I thought of the saddle weights used for horse handicap racing.

Then I thought, "That's gotta be a big rocket."

Then I thought, "You're an idiot, Skippy."
 

Spacey

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It's weird (or I am). I saw 'Derby weight' and I thought of the saddle weights used for horse handicap racing.

Then I thought, "That's gotta be a big rocket."

Then I thought, "You're an idiot, Skippy."
I am still unaware of the correct term 😩😂
 

Spacey

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Yes, level 1 Certified!!! No unfortunately not this launch, those sound very interesting, hmm 🤔 maybe in the near future for level 2. Ended up going with a h-115 with an 8 second delay. Only issue I faced (which you guys informed me of) was my parachute didn’t fully open, slightly tangled around my nose cone eye bolt, didn’t cause any damage and landed right next to the launch strip.

Thank you again!! Y’all are awesome!
*will upload launch video once it’s pulled from the camera. 🚀😊
 

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samb

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Yes, level 1 Certified!!! …
Congratulations. Very nice build, glad you recovered it. I think the tangled chute may have been a blessing in disguise. A fully open canopy at 2000+ feet would likely not have landed at the end of the launch strip. You’d have gotten to test your tracker I think. :)
 
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