So I'm making a rocket which apogee's is 6233.60 ft, max velocity is 213 m/s and max acceleration is 72.5 m/s^2. So problem is my nose cone doesn't fit so well in body tube. I can feel the ledge when I touch between nose cone and body tube and the ledge is nearly 1mm. Is it a big problem?
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Which part is the "ledge" on? Nosecone or body tube? If it's on the body tube, then that will increase the drag. However, 1mm is not too bad. Do you have a nosecone that's meant for a thin wall body tube, and you have a standard wall thickness body tube? Post an image of the coupling. Does the nosecone coupler fit properly in the body tube?
You could sand the edge to profile it to match the other edge.
You could sand the edge to profile it to match the other edge.
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need pictures of what it looks like
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How thick is the body tube? Assuming the nose cone is actually conical as drawn, it should work fine to just sand it to match the taper of the nose cone, or even blend the transition with a radius. Won't be as good as if the seam was at the full OD of the tube, but much better than a step. Work on making the edge of the cone and the edge of the tube both very clean and crisp to minimize the disruption caused by the seam. Fortunately, at 213 m/s, you don't have to worry about any transonic/shock wave issues.
I'm not going to sand if it's not necessary because I already painted the rocket. However If it's necessary I will sand the edge.
Thickness is nearly 2mm fiberglass
To be honest my drawing is terrible so it's not conical actually it's power series and the parameter is 0.7
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That power series is a secant ogive, so I'd go ahead and sand it.
It won't matter at all, it just won't go as high. Maybe it'll go 6150' rather than 6233'.
If that minor reduction in altitude is important to you, then sand it.
If that minor reduction in altitude is important to you, then sand it.
So you're saying the rocket can't wobble and crash because of something that small.
Correct. Much larger imperfections are minimal when it comes to stability. It's just extra drag.
You could, in fact, add that exact "ledge" into OpenRocket to see the exact effect it would have.
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I think it will fly just fine as long as the nose cone fits tight enough that it won't drag separate. If you want to fix it, you could either sand the top of the body tube as others have suggested, or, depending on the NC material, use some Bondo Glazing and Spot Putty to build up a fillet on the bottom edge of the NC.
