Almost there. Sanded the CWF (difficult in those confines) and applied thin CA to harden the surface. Ready for paint.
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Alcubierre Build Thread
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Finished.
THe first picture shows that I didn't do as good a job shaping the filler as I thought I did. Sort of a lump in the side of the ring there. Also, my brush paint job is predictably crappy. It could use another coat (or two!) of cranberry, and some silver touch-ups, but I don't think I'll bother.
At minimum, it sure looks better than when we started, and it should be structurally sound. Ready to fly again!
THe first picture shows that I didn't do as good a job shaping the filler as I thought I did. Sort of a lump in the side of the ring there. Also, my brush paint job is predictably crappy. It could use another coat (or two!) of cranberry, and some silver touch-ups, but I don't think I'll bother.
At minimum, it sure looks better than when we started, and it should be structurally sound. Ready to fly again!
lakeroadster
When in doubt... build hell-for-stout!
Nicely done..
Yes, that looks good, like one of those things most people wouldn't notice unless you pointed it out.
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Totally agree.
If you are going to dare fly her again, she will pickup more nicks and scratches during the next flight (always happens), and you can get back to smoothing a few remaining lumps during the second round of repairs.
If you are retiring her to a stand on a shelf, no-one will see that bump from 3 feet away!
a
Gotta fly! I really want to see it going up again. I may swap in a nylon chute for future flights. But in any case, she will go up again at the next launch I attend, whenever that is.
Now you did it. I want to upscale this to a 3 inch body tube with a 54mm mount. Can you share your openrocket file? Pretty please???
Nytrunner
Pop lugs, not drugs
What is that, an 8" ring?
11.3” ring! A slice of sonotube maybe? Eh, probably too heavy, but who knows.
Anyway: hell yeah! I’ll pm the details.
Anyway: hell yeah! I’ll pm the details.
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I looked back in time (this thread and the half-baked one) and didn't find the length. It looks, though, like if the ring scales up to 11.3" then the airframe would accommodate a rather long 54 mm case. CTI 54 mm 4 to 6 grain motors mostly have peak thrust between around 130 and 400 pounds. Aerotech has a bunch in the same range. So I think some sonotube won't be a problem.
Nytrunner
Pop lugs, not drugs
Long 38s should work too since they have the long core with plenty of burning surface area
Based on PMs with SDramstad it'll be a bit smaller than that: 2.6" airframe, 9" ring, and he'll be employing composites in some form or other. So the question is moot.
My concern over the weight of the sonotube ring was not total weight of rocket, it's having a big chunk of weight at the back. With a very light balsa ring I still needed a bit of nose weight on mine.
At this point we can await further build info from SDramstad whenever he is able to get this started.
My concern over the weight of the sonotube ring was not total weight of rocket, it's having a big chunk of weight at the back. With a very light balsa ring I still needed a bit of nose weight on mine.
At this point we can await further build info from SDramstad whenever he is able to get this started.
Nytrunner
Pop lugs, not drugs
Sometimes noseweight is just what ya need. Fact of the hobby
Yup, that's fair, good point.
I still may go with a 3 inch body tube. Can make the ring by using sonotube as the mandrel then slide the ring off when set. Am a bit concerned about a 54mm motor. You dont want to go transonic with a ring in the back. I shredded a carbon fibre ring fin on a 38mm min diameter rocket with a G80. Shredded so bad it took over an hour to find all the pieces......
I would think you'd be more comfortably in 38mm territory there, but I've never flown bigger than 29mm so who am I to talk. 
So I take it you mean as the mandrel for laying up FG or CF?
Has anybody tried reinforcing a composite like that with steel wires? Maybe lay up a layer of cloth, then lay up chicken wire fencing, and then more glass over that?
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If I was going to try something like that I think I would go with aluminum hex mesh or similar.
Carbon fiber is stronger then steel and wont rust on you. If you want to get fancy a nomex hex cell material would probably work but its real pricey. I am probably going to use balsa sheet sandwiched in carbon fiber. It comes out surprisingly strong and light.
Ah, but the big question: have you decided if you are you going to install the ring in one piece, or split it like I did? Having gone through it one way, I'm not sure how I'd choose if I were to do it over again. Either way has its pluses and minuses....
Maybe cut a slit halfway through the ring and a corresponding slit halfway through the wing and slide them together. I like the idea of keeping the wing in 1 piece and the ring in 1 piece.
Bruiser
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How about a wrap of 1/64th ply over a form, followed by a layer of foam, then another wrap of 1/64th ply. Then add on the leading and trailing edge with balsa. This is how RC modelers build foam wings. It can make for a light weight wing. I just don't know if the foam would wrap well or not...
-Bob
-Bob
That'll take some careful measurement and cutting, but should work great. I was too nervous to try that on mine.
Nytrunner
Pop lugs, not drugs
That is very similar to the Estes Curviliniear
Go for it!
Go for it!
Build the ring first then cut the slits in the ring. Rough out the wings and make the cuts before the wings have been finished. Before putting the carbon fiber on them and before painting. also leave a little extra material on the fin tips and cut them down as needed to make the ring fit. Once everything fits you can do the tip to tip carbon and finishing work.
Thanks. All eyes on @SDramstad for the upscale now!
302% upscale to 4" diameter with a 54mm mount . . . K550 !
Dave F.
Dave F.
That'd be a 15" ring... I'd pay airfare to go see that thing launch.
I'd pay airfare to go see that thing launch. Similar threads
