#11
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I expect he means Centuri ST-20 tubing (which is/was available from eRockets/Semroc). It’s 2.0 inches ID with a .021 wall thickness.
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Bernard Cawley NAR 89040 L1 - Life Member SAM 0061 AMA 42160 KG7AIE |
#12
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Quote:
BEC is correct, it's a Centuri #20 from eRockets, 2.042" OD | 2.0" ID | 0.21" thickness. Motor tube is a #9 (basically a 24mm) 0.998" OD | 0.950" ID | 0.024" thickness. Centering ring: Semroc CR-9-20, nose cone: Semroc BC-2025. IIRC the front of the body tube was 2.5" from the leading edge of the upper "fins". The end of the tube was about 0.5" below the trailing edge and the motor protruded another 0.5" beyond that (the pic wasn't to scale, just my initial sketch, which is why I put dimension callouts to remind myself). Quote:
I just wanted it to look like a box kite and launch straight and safely. In reality it almost DID fly like a kite when it would get sideways, which was never the intention of course. Can I get a copy of your Rocksim file? (Just started learning how to use OpenRocket and I believe it can read Rocksim files). It would really help me end up with a stable, flyable design.
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“I would like to die on Mars. Just not on impact”. — Elon Musk “Minds are like parachutes--they only function when open”. —Thomas Dewar |
#13
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Quote:
I have attached a RockSim file (Cubix-plans .rkt) based on the dimensions and other information you posted. Unfortunately this simulation uses pods which are not compatible with Open Rocket software. Open Rocket is currently unable to simulate this type of complex design. RockSim can handle the geometry but doesn't take into account the interference from the upper set of box fins on the lower set. Removing the upper set of box fins will give a stable design. I don't know if there is a trial version of RockSim available. I suggest you ask Apogee Rockets, they used to give a 30 day free trial. The software now costs $123.60.
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Bruce S. Levison, NAR #69055 |
#14
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Much thanks Bruce!
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“I would like to die on Mars. Just not on impact”. — Elon Musk “Minds are like parachutes--they only function when open”. —Thomas Dewar |
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