View Single Post
  #27  
Old 06-02-2005, 01:32 AM
CPMcGraw's Avatar
CPMcGraw CPMcGraw is offline
BARCLONE Rocketry
 
Join Date: Mar 2005
Location: Mobile, Alabama
Posts: 5,357
Default

Quote:
Originally Posted by John Brohm
Craig;

I've not updated my RockSim yet- two fins or three? If two, I'd be a little concerned with the sturdiness of the ring fin. Your view?


I chose two; The shapes of the support pylons were originally curved on the leading and trailing edges, to form the "stock" of a standard "six-shooter". If you look at the model with the fins top and bottom, the body tube was supposed to resemble a lawman's peacekeeper...

Limitations of the simulator prevented me from drawing that shape completely as I wanted...

Having said that, your comment about sturdiness is interesting. I thought about the possible vibration of the ring as I drew this up, but considered it a lesser problem given the smaller motors I intended to use. Perhaps if you add two thin, narrow pylons inside the ring toward the center, so that they're not seen in profile, maybe that would keep the ring from fluttering. Another possible solution is to glue two doublers at the ring-to-pylon joint, both sides, to reinforce the joint. Might be you could get by with two strips of cardstock, folded down the middle, and glued right into the corner on both sides, like a piece of welded angle stock...

One thing I was trying to avoid was to make it look like the Estes Sprite.

Quote:
And what do you think about bumping this one up to say a BT-50? Then you could bring in the PNC-50SP nose (Argosy, Venom), or the P/N 071005 nose (Star Rider, Nemesis). Could be slick.


Like going from a peashooter to a "Dirty Harry Magnum"? How large would the ring fin need to be to stay in proportion? I haven't looked at that yet, but I might. Interesting idea.

Craig
Reply With Quote