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Starship Avalon: build thread

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neil_w

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Contents
This thread started as a design exploration, but evolved into a real build. For those who want to skip the preliminaries, here's where things happen:

  1. Design exploration starts here (this post)
  2. Build preparation officially started at post 91 (although I also did some fabrication experiments starting at post 60).
  3. Actually construction starts at post 143. :p

Here's what I'm building:


Original first post

Trailer for the new movie "Passengers" just came out. Movie looks interesting, but I really love the design of the ship they're on. Here's a direct link to the point in the trailer where the ship sails by:
[video]https://youtu.be/7BWWWQzTpNU?t=46[/video]

Here are three still shots, from front, side, and behind.
avalon_front.jpg

avalon_side.jpg

avalon_rear.jpg

It's very hard to see, black ship against black space; I still don't fully have all the details of how it's worked out, although I think I get it overall. Building a faithful recreation is way beyond my pay grade, but I'm gonna see if I can capture enough of the essence to be worthwhile.
 

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dhbarr

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Looks like a ring-tailed rack rocket in the back, standard mid, needle fore, triple helical wing surfaces.

I'll bet you could carve them out of a CF tube as long as it had significant fore-aft UD layering.

Convolute might work, filament wound almost certainly not, cloth wrapped maybe?

At any rate, very neat.
 

Gary Byrum

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It's very hard to see, black ship against black space; I still don't fully have all the details of how it's worked out, although I think I get it overall.
Next time, let me know you need a little enhancement.

Starship Avalon 2.jpg

Starship Avalon.jpg

Starship Avalon 1.jpg
 

Screaminhelo

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Step 1 may involve recreational pharmaceuticals that are inappropriate to discuss on the boards here.

Step 2 repeat step 1 until "The Wall" makes perfect sense.

Step 3 Break out the CF and epoxy and get to it!

I can actually see a way to build this pretty faithfully to the movie image using carbon fiber tubes but Stability will be a problem this way. I do see some inspiration for less than conventional "fins" here. I am wondering if a vortex arrangement like this would actually be effective.
 

rstaff3

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Wow, that one is going to be a challenge. Probably several.
 

neil_w

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Next time, let me know you need a little enhancement.
That seems a rather personal thing to discuss here on the forums....


Oh, you mean the *pictures*... ah well thanks for that, dunno why I didn't even think of doing that myself. :facepalm:

I'll bet you could carve them out of a CF tube as long as it had significant fore-aft UD layering.

Convolute might work, filament wound almost certainly not, cloth wrapped maybe?
Step 1 may involve recreational pharmaceuticals that are inappropriate to discuss on the boards here.

Step 2 repeat step 1 until "The Wall" makes perfect sense.

Step 3 Break out the CF and epoxy and get to it!
I'm pretty sure I don't have sufficient quantity of said pharmaceuticals or composites expertise (in both cases, my quantity on-hand is zero) to attempt to build a faithful recreation of this thing, and I have no idea how it'd ever be flyable anway. I'm just trying to get some inspiration for a slightly more conventional rocket, i.e. one that I might actually be able to build and fly. My initial experiments in OR are pretty uninspiring and fail to capture the essence of this; I'll have to noodle around some more to see if I can do better.

I certainly would love to see someone have at it with composites and see what's possible, though. I find the design to be quite beautiful, even if largely divorced from reality.
 

Gary Byrum

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Looking at the design reminds me of, "Too much forward fin is a bad thing". This space craft looks to be embraced entirely of the (would-be fins) and not adequate for stabilization. This is familiar to me when I designed my Time Warp rocket. Looks cool, but flies terrible. Simply because there is too much fin in the forward area. Had I extended the airframe, I might have had more successful results. This space craft looks like a flying fin can. You could use this craft design and apply it to a longer extended version. Just triple the length with some artistic "Neil Logic" airframing and a slick nose & cockpit, and you might go somewhere with this. You could also use a 4" (or so) tube to carve your fins out of.

Here's the Time Warp.

DSCF3145.jpg

Here what the tube fins look like on my Gyro Dragon.

DSCF3385.jpg

DSCF3471.jpg

Here a makeshift template layout for the Avalon using a 4" CA treated tube.

Starship Avalon.Fin.jpg
 

neil_w

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I agree completely, this thing is basically a flying fin can, and I'm trying to figure out if I can design a fin can that captures its essence, and then an interesting enough rocket to go with it. My current design experiment would require roughly 6.5" tubing to cut the helical fins out of, which would be difficult for me to pull off (the diameter of the tube needs to be large enough to look good as the outermost fin component; too small and it'll require more fins extending beyond it. Maybe that'll be where I end up, eventually...)

Lotsa head scratchers here.

I'll post a picture as soon as I come up with something even slightly appealing, not there yet.
 

Gary Byrum

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My current design experiment would require roughly 6.5" tubing to cut the helical fins out of, which would be difficult for me to pull off.
Actually, that's a much easier part than you might think. Just requires some patience. First off, make a foam/sponge mop on a dowel, soak in CA and swab the hell out of the 6"?, tube inside. Coat the crap out of it too, because once you trace the fin template on the tube, you'll need to cut it out. I used a jig saw for the rough cut and hand sanded them down smooth. Treating the edges with CA and sanding again. Pretty darn strong Neil. My Gyro Dragon has flown 6-7 times with no fin issues.

Mounting these fins are going to be problematic with so little to attach them with, (per the design pictured). It has FRAGILE written all over it.
 

neil_w

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Yeah, I would plan to have this whole thing be a lot beefier. The design as shown is incredibly spindly and would have (IMHO) no chance at holding together. Again, I'm looking to capture enough of its essence and create a nice design, rather than actually recreate it. I don't know if that's possible yet, at least to my satisfaction. Should give me some good brain exercise before it's all through.
 

TomSmith58

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For a design like this the "find" are on the ends of standoffs or pylons. The lighter the find are the lower the possibility of flutter. The helical fins must be stiff and light and the pylons must be stiff. It's ok from a flutter standpoint if the pylons are heavy.

I can't see from the pictures; are the fins each supported by two pylons? One at either end? That's important. One pylons won't do it.
 

TomSmith58

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If the fins are hollow they will look more like the movie and they will be stiffer. I can see now from the pictures that the fins have two pylons.

Hollow fins could be light and stiff. The problem is how to make them. One could carve a wooden blank and make female molds from that to make two fiberglass halves to glue together. Light and stiff.
 

EXPjawa

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As a tangent, I'd be curious to know what the logic was behind the design as configured. It looks cool, but seems kind of curious from a functional point of view.
 

EXPjawa

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Well, sure, but in a lot of cases, there is at least some sort of design justification for the layout of sci-fi spacecraft. The prop designer or whatever the equivalent is had some sort of thought train that dictated how it came out. That's the sort of thing that people geek out on. But of course, it could simply be that they thought it looked cool. Frankly, I have to believe that coming up with a novel space ship design that doesn't look somehow derivative isn't easy. Especially given how many sci-fi movies/shows/comics/etc that have been produced over the years...
 

neil_w

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I agree completely.

In this particular instance, though, while I can imagine that some of the individual design details are perhaps justifiable in some way or another, the whole thing looks more like a "fantasy" design than a "science fiction" design. In any case, IMHO they have done an excellent job coming up with something novel and beautiful, even if would be a bit (!) hard to justify in the real world.

Speaking for myself, I don't think much about practical considerations when designing LPR stuff. I just go for something that looks good, and will fly correctly with some BP up its butt.
 

EXPjawa

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I'd agree on all of that, though I try to have some sort of quasi-engineering justification (even if it involves fictitious hyperdrives made from Unobtaineum) when I lay something out. I'm not fantasy-minded enough to let myself come up with something that's pure whim. This ship does, however, remind me (faintly) of some of the more other-worldly Estes offerings from, say, the mid-70s to early-80s, like the Starlab, Alien Explorer, Andromeda, maybe the World Federation Star Probe. Though, obviously, this thing is a different level of crazy... :) Its hard to tell from the screen shots how far along the center spine the helix pods are; the nose could extend pretty far ahead of them.
 

neil_w

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Here's my first take, output from OR. I made it all black and now it's hard to see again, but I'm not going back and changing everything again (very tedious). I made the rings dark grey instead of black because otherwise they almost completely disappeared.

Sorry if this is a crushing disappointment to those who were hoping for a sculptured composite masterpiece. :wink:

Side:
avalon_or_side.png
Rear:
avalon_or_rear.png
Front:
avalon_or_front.png
Fin can close-up:
avalon_or_fincan.png

Needs some more detail in the front half of the rocket, and some decals. No idea if it would be even close to stable, or if it would hold together. I'd presume to use some thicker wood for the pylons, maybe some 1/8" balsa or something like that.

All comments welcome, this is really just a rough draft at best. It's interesting enough to keep working on, I think, and I think it captures at least some of the flavor of the original.

Oh, I attached the OR file if anyone wants to noodle.
 

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Gary Byrum

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Fin can looks a little large for the drawing. You're off to a good start though. Prolly fly fine with the right nose weight.
 

Gary Byrum

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Here's me "noodling".....In AutoCAD, I'd shorten the fin can with the given airframe. Then I might fatten up and lengthen the airframe with the given fin can. Once I feel the balance between the two, I might tweak the fin can a bit to play with different ideas.

Just me noodling.
 

rstaff3

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Well, after seeing the first cut at this, it certainly seems doable. I wasn't that sure when I saw the screen caps. You will have a very unique creation.
 

neil_w

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Here's me "noodling".....In AutoCAD, I'd shorten the fin can with the given airframe. Then I might fatten up and lengthen the airframe with the given fin can. Once I feel the balance between the two, I might tweak the fin can a bit to play with different ideas.
Getting the proportions correct between the fin can and airframe is the hardest part here. I need to fiddle with it some more for sure. Unfortunately those simulated helixes are brutal to fiddle with in OR (being made up of 11 separate pieces) so it inhibits quick experimentation. But I don't have the CAD chops to do it there either, so....

I feel like the front of the rocket needs to be more than just a long tube, but I'm not quite sure what sort of stuff would look good in conjunction with the crazy fin can.

Well, after seeing the first cut at this, it certainly seems doable. I wasn't that sure when I saw the screen caps. You will have a very unique creation.
Dunno what the odds are I'll ever actually build this design, but it is an interesting exercise, and interesting exercises are what keep my rocket neurons from atrophying when I'm not building. :)

Or maybe I should just go build a Black Star Voyager and be done with it?
 

neil_w

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Compressed the fin can a bit, and lengthened the front section. Added back sweep to the rear pylons and forward sweep to the ones in front, overall effect is to move the helixes backwards. Oh, and.... OPEN AIR MOTOR MOUNT BABY!



The second picture (fin can close-up) also shows some little finlets I added to the rear of the helixes, just so there'd be something guaranteed to break off each flight in the unlikely event that the entire rocket didn't shred on the way up.

Dangit, the black really makes it hard to see anything. :(

Proportions still not quite right, but better?

avalon2.png
 

rstaff3

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Looks good to me. I like the air-cooled motor mount! I actually don't mind the 'pixelated' fins :dark:
 

neil_w

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Hmm, with a little paint and decal work it starts to look like something. Gotta figure out what to do (if anything) at the front.


avalon_photo3.png
 

GlenP

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The pixelated or faceted fins of your artwork may inspire a building technique. Use a larger diameter tube like an oatmeal can as a mold, cover with wax paper, and laminate smaller squares of overlapping thin balsa sheet to rough out the shape. Then sand the heck out of it. Then you might strengthen the balsa with cardstock, like papering fins.
 

neil_w

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The pixelated or faceted fins of your artwork may inspire a building technique. Use a larger diameter tube like an oatmeal can as a mold, cover with wax paper, and laminate smaller squares of overlapping thin balsa sheet to rough out the shape. Then sand the heck out of it. Then you might strengthen the balsa with cardstock, like papering fins.
That is a very interesting idea. Seems quite possible. Maybe a ton of work, but if I ever build this thing it'll be a long slow one so what the heck. If the final product retained some of the faceting (my "pixelated fins" lol) it might look cool.

Loooong way to go here but the whole thing is starting to seem plausible.
 

grapetang

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Looks like a ring-tailed rack rocket in the back, standard mid, needle fore, triple helical wing surfaces.
Very cool! I think dhbarr nailed it! That's what I'd attempt.

I don't think OR will sim inner tubes nor the helixes correctly. With a C6-3 in place, your CG & CP fall on top of one another, and with suitable nose weight, you might need to use a 24mm mount. Do a swing test with a mockup, or sim without the helixes?

I like what you have so far. Looking forward to the progress!
 
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