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As much time I've spent researching model rockets, I have a few HPR questions that I've yet to wrap my head around. I'll admit, I've not spent much time trying to answer these questions myself (I'm really sleep deprived right now).
I know that NAR frowns on metal being used for model rockets, but at what point of certification does that go by the wayside? I've seen HPR builds with sharp pointy metal nosecones, I've seen BBs mixed with expoxy to create noseweight... When is that OK, and you're not voiding your protection (insurance coverage) with using them?
Why do I ask? I've got a 4" design (a stubby pencil design) that I'd like to use an empty metal cigar tube (Cuban of course) to form the "point" of the pencil. I could use the handle of a broom for it, but that would be harder, stronger, and heavier than this little lightweight piece of aluminum.
I realize that the 5:1 nosecone refers to a ratio... I'm presuming 5 (whatever the units are) to 1 (whatever the units are. Is the 1 the radius? or the diameter? Basically, how long would a 4" OD 5:1 (ogive) nosecone be? 20"? 10"?
Now, it's time for bed.
Thanks!
I know that NAR frowns on metal being used for model rockets, but at what point of certification does that go by the wayside? I've seen HPR builds with sharp pointy metal nosecones, I've seen BBs mixed with expoxy to create noseweight... When is that OK, and you're not voiding your protection (insurance coverage) with using them?
Why do I ask? I've got a 4" design (a stubby pencil design) that I'd like to use an empty metal cigar tube (Cuban of course) to form the "point" of the pencil. I could use the handle of a broom for it, but that would be harder, stronger, and heavier than this little lightweight piece of aluminum.
I realize that the 5:1 nosecone refers to a ratio... I'm presuming 5 (whatever the units are) to 1 (whatever the units are. Is the 1 the radius? or the diameter? Basically, how long would a 4" OD 5:1 (ogive) nosecone be? 20"? 10"?
Now, it's time for bed.
Thanks!