ogivemeahome wrote:A suggestion. Include a small spigot on the internal side to mate with vent holes in the airframe. This would help prevent any relative motion between airframe and guide. Increased complexity, yes. Worth it, don't know.
Great idea. Given the explosion of interest in 3D printing, you may have trouble protecting the idea.
Best of luck. Have a great time at Thunda.
Thanks for the suggestions! I'm working on various ways of preventing slippage for a longer airframe which may need support more forward of the fins. I've thought of using some sort of spigot/pin to hold them in place, but that requires a standard airframe configuration and a lot of testing. It is one of the many solutions I am pursuing.
As for protection, I acknowledge that (1) I didn't invent the fly-away rail guide, although I think I can claim to have invented the hinge mechanism which creates non-linear spring forces and reduces rail friction, (2) I could never sell enough rail guides to justify the cost of a patent, and (3) I can't stop someone from doing it.
On the other hand, (1) I have them priced at a point where you'd have to spend more time and money developing and printing failures than it would cost you just to buy some (you should see the pile of failures I have), (2) I can't see someone sane deciding that the pie is big enough for them to invest all the time and money required to divide it (in fact I question my own sanity on this), and (3) The rocketry community is pretty small and generally discourages that sort of thing. I'm definitely not getting rich on rail guides. They might buy me a few motors.
Sadly, I'm not going to make it to Thunda, and am relying on Crazy Jim to do some testing down there. I actually lived in Australia (well, Tasmania...) for a while as a kid and have been back a couple of times, but not since visiting Sydney on business in 1999. I want to get down there again sometime.
Bill Cook _/)_