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You could crank the wings back a bit and still keep the look but move up back.
Indeed, you are correct. I should like to amend and amplify my previous. It gets fiddly and frustrating when trying to conform a fin to a transition with something different from a conical cross-section. I am really hoping that you will now correct me on this too.
You could crank the wings back a bit and still keep the look but move up back.
I don't think you are looking at rockets designed for altitude.EDIT: and might I suggest beveling those fins, according to OR, it adds 100 feet to my Ap.
I don't think you are looking at rockets designed for altitude.
Those are very cool
I thought about shark teeth.
Are you printing decals in white? That's the one thing I can't do, and its a severe limitation
and "oddroc's ??"
EDIT: and might I suggest beveling those fins, according to OR, it adds 100 feet to my Ap.
You have drawn out a Daddyisabar goonie photo gallery! Thank you on behalf of all of us who appreciate oddroc porn. Now go start another thread and ask about tractor motors.
I don't think you are looking at rockets designed for altitude.
I only gave him the soft porn. Nice, cute, stubby airplane like oddrocs with asymmetrical fins. All based on Baby Berthas or cute Spaceship One models. The hardcore stuff is in other threads. Even hinting on the subject of tractor motors here is forbidden.
Once you get the double-secret password, you can see the hard stuff. Merely seeing them will kill the weak and drive the strong mad. Crazy stuff like a Lancaster with 10 (?) LPR motors. Be warned.
Question on rear blow:
(haven't done it before)
The engine tube is 6" long and goes all the way to a bulkhead at the nosecone. There are 2 centering rings (fore and aft) and the chute and shock cord will be wrapped around the engine tube (loosely). The whole thing is a piston and blows the whole 6" tube out the back. Got that.
No wadding right? The hot gasses are isolated in the "combustion chamber" of the piston.
Does the bulkhead need any protection? I'm thinking of gluing a piece of aluminum foil to it a blast shield.
The inner surface of cardboard body tubes are typically exposed directly to the ejection charge exhaust with little damage -- so if your bulkhead is at least as fire-resistant as cardboard it should last for a few launches.
Foiling the bulkhead might actually make it hotter in the ejection cylinder forward of the engine. Some fraction of the heat transfer will be by radiation, rather than conduction by contact with the hot gas. Putting a reflector on the bulkhead will increase the radiant energy incident at some other surface. If you are worried about it, a high heat black paint or a piece of some fire-resistant cloth, might be a better choice than aluminum foil.
bulkhead is (currently) paper-covered balsa.
My 1st thought was high-temp paint. I don't seem to have any around the house. And I'm not buying a can for 1 square inch.
I could give the foil a spritz of regular Rustoluim enamel. that would address your reflected heat issue, and still give me my metal barrier.
bulkhead is (currently) paper-covered balsa.
My 1st thought was high-temp paint. I don't seem to have any around the house. And I'm not buying a can for 1 square inch.
I could give the foil a spritz of regular Rustoluim enamel. that would address your reflected heat issue, and still give me my metal barrier.
What about a layer of glue, like a decent epoxy, or JB-weld, or even a good layer of TB?
I don't know if anyone touched on this, I didn't take time to read every post.
But I think you want to section those wings or cross grain ply them.
With the wood grain showing the way it is, if it scoops the wind at all it would take a lot of pressure on the point and could snap off.
But I think it looks really, really cool! I too would love to see a video of this fly.
Maybe lengthening the air frame and moving the nose cone forward a bit.
Question on rear blow:
(haven't done it before)
The engine tube is 6" long and goes all the way to a bulkhead at the nosecone. There are 2 centering rings (fore and aft) and the chute and shock cord will be wrapped around the engine tube (loosely). The whole thing is a piston and blows the whole 6" tube out the back. Got that.
No wadding right? The hot gasses are isolated in the "combustion chamber" of the piston.
Does the bulkhead need any protection? I'm thinking of gluing a piece of aluminum foil to it a blast shield.
Right, no wadding and although you can glue aluminum foil on the bulkhead, simply coating it with epoxy is all the protection you’ll ever need. For that matter you probably don’t even need to do that. The ejection charge is very short duration and unlikely to burn the bulkhead.
Thanks
New question:
Where does the forward shock cord mount go?
I can't put it in the "combustion chamber" of the piston, it'll burn the shock cord (and might zipper the tube), and if I put it in the aft of the main tube, the forward centering ring of the rear blow section will "trip over it" on the way out.
I guess I could put it in the aft of the main tube, between two fins so when it does trip over it, it pivots the rear tube safely between the fins.
Where else can it go? Am I missing something here?
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