- Joined
- Aug 27, 2011
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well, first rendition isn’t quite working right.
maybe trying to do too much with one rocket.
looking for something marketable (not that I am ever going into business, but one of my “dreams” is to come up with a design that gets picked up by Odd’l Rockets, FlisKits (is @jflis even doing new designs), Semroc, ERockets, Estes, Apogee)
obviously something different and funny.
cheap (hence the ping pong ball nose cone, since I have read that nose cones are the most expensive part of most low power kits, although with question of worldwide balsa shortage that may change)
low power
i like asymmetric fin rockets that corkscrew, I consider corkscrew flights entertaining as well as a way to keep altitude low with flight time high, kind of like saucers with a literal twist.
also was hooooooooopppppping that could achieve backslide recovery, that may be too much.
anyway, I don’t know how to use open rocket (I know, I should just use it), but I am also in doubt of the Accuracy of Sims for a ping pong ball nose cone. I also suspect the CP Effect of a ping pong ball nose cone is partially dependent on the size of the tube it is attached to. Big tube you essentially have a hemispherical cone, little tube you literally have a ball.
anyway, I did @lakeroadster ‘s swing test, and it WAS stable…….backwards. Consistently backwards.
for those that want to play with this.
ping pong ball is 4 cm diameter, mine weighs 2.6 Grams although per Google it should weight 2.7 grams.
tube is standard BT-5, 18” long.
ring fin is BT-60, 1.5 inches long.
with an A10-3T total weight is 20 grams, and the CG with 1/4 of motor hanging out the tail is 6” from tail of BODY tube, which ends lined up with the ring fin.
i have a paper straw launch lug on inside.
i am pretty sure I am going to need a bigger diameter ring fin.
i am TRYING not to add nose weight as I am hoping for Back Spin recovery.
ideas anyone?
once I have a workable design I will poke holes in the ping pong ball, the launch rod will go THROUGH the ball.