The BNC-55AO balsa nose cone is available from eRockets:

http://www.erockets.biz/semroc-bals...l-sem-bnc-55ao/

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Lee Reep
NAR 55948, L2

Projects: Super Sky Hook, Estes Saturn V, Astron Farside-X
Stuck In the Paint Shop: Estes Saturn 1B
Completed!: Painted Prowler! (ditched the pink tube wrap ...)

Thanks. Color me embarrassed. Just after I posted my question, I noticed another Goblin thread that contained the answer. I even dug in to my stash of SEMROC parts and discovered at BNC-55AO! Now, another question - if I swap out the plastic cone for the balsa, will nose weight be needed?

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Got a Caribbean soul I can barely control.....

I have an original from the early 70's and it doesn't have any nose weight added. I think it would depend on what type of streamer you use. Mine is crepe paper and maybe 7ft long. When coiled it has some substance. If I was going to use a shorter, plastic streamer I would most likely put a washer under the screw eye.

Thanks, sounds good! Might have to try the old string stability method . I can see it now. Our neighbors wondering why their 63 year old neighbor is whipping a rocket around his head!

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Got a Caribbean soul I can barely control.....

I would suspect the stock Goblin is a very, very stable design. Those are some pretty big fins, and I would almost conjecture that it might be stable with just three fins (mounted in a standard three fin 120 degree configuration).

But, checking via a swing test or some CP/CG calculations won’t hurt. The quickie ‘cardboard cutout’ CP test would be easy on this one.

Earl

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Earl L. Cagle, Jr.
NAR# 29523
TRA# 962
SAM# 73
Owner/Producer
Point 39 Productions

Rocket-Brained Since 1970

www.jonrocket.com has the BNC-55AO in stock at a good price.

Thanks! I dug up a copy of the original Estes kit instructions, and there is no nose weight listed in the parts list. So I'll still check the stability but I think we're good.

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Got a Caribbean soul I can barely control.....

Guaranteed that a properly filled/sealed/sanded/painted BNC-55AO weighs more than a PNC-55AO.
You will not have any stability issues with the balsa cone.

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When in doubt, WHACK the GAS and DITCH the brake !!!
No Harm=NO Foul advocate

If you are NOT FLYING LOW in the left lane, you need to GET THE #$&@ OUT of it !

Yes, there is such a thing as NORMAL, if you have to ask, you probably aren't !

The Semroc version doesn't have nose weight either, and it flies fine on D12-7s. I tried an E12, but it went KABOOM on the pad. Entertaining, in any case!

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Paul
If we weren't all crazy, we would go insane - Jimmy Buffett
NAR #87246 www.wooshrocketry.org

Thanks!

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Got a Caribbean soul I can barely control.....