Alcubierre Build Thread

Discussion in 'Scratch Built' started by neil_w, Sep 27, 2018.

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  1. Mar 7, 2019 #271

    Gary Byrum

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    HERE HERE! I 2nd that notion.
     
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  2. Mar 9, 2019 #272

    BABAR

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    3rd!
     
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  3. Mar 10, 2019 #273

    neil_w

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    Weather yesterday was a bit cold but dry and calm, so I took a slight risk and applied a new cranberry topcoat to the rocket. It looked to me like a pretty clean coat, we shall see when it is dry. I'm gonna give it plenty of time. Next step is the silver.
     
  4. Mar 14, 2019 at 9:39 PM #274

    neil_w

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    Took advantage of a nice day to paint a sheet of decal paper silver. It didn't come out perfectly even, but I think it's OK.
    silver.JPG

    The picture exaggerates the unevenness for some reason.

    Anyway, I've never tried this technique before so we'll see how it goes. Got the idea originally from a post on @hcmbanjo 's blog. It'll be a while before the main rocket is ready for these (need to paint the silver coat first, that should be within a week or two I hope) but I can do the shield at the front of the nose cone as soon as this sheet is fully dry.

    Presumably I don't need to clear-coat before applying decals, because the paint coat is waterproof. Should be interesting.
     
  5. Mar 15, 2019 at 12:59 AM #275

    neil_w

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    I snuck out to the shed to take a peek at the new cranberry coat, and frankly it looks fantastic:
    newcranberry.jpg

    It is very smooth and glossy, about as good a top coat as I can reasonably expect to do (better in real life than that picture). I think that for small rockets like this, about 90% of the trick to getting a good gloss paint finish is simply to sand the rocket down before the final heavy coat. I rarely get a clean finish when I do three coats at once, row, but whenever I've put a top coat over a sanded base I've gotten great results.

    I'll give this one a while longer before I bring it in and start masking it for the silver coat. Unfortunately there is no good painting weather in store for the next week.
     
  6. Mar 15, 2019 at 5:20 AM #276

    BABAR

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    Looks slick. Literally!
     
  7. Mar 15, 2019 at 8:03 PM #277

    neil_w

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    I rather suddenly became nervous about my silver decals, because I remembered the last time I peeled of masking tape from a silver coat. When the tape bends tightly, the metallic paint on it disintegrated into flakes. That's not good for decals which need to be flexible. So, as always, I did a quick test: I cut off a small piece of the silver, and attempted to affix it to a pharmaceutical bottle I had nearby, reasonably close to the diameter of a BT55. The decal seemed pliable, and released from the backing paper nicely. A few minutes after application, though, I noticed the edges starting to lift. Uh oh.

    So I used a another small plastic bottle (very smooth) to burnish those edges down. To my pleasant surprise, this time they stayed, and the end result is darn near perfect:
    silvertest.JPG

    Everything stayed down and it looks great. Perhaps I might have trouble with the little shield near the tip of the nose cone (tight bend radius there); if so I'll just get rid of it. Other than that, good to go.
     
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  8. Mar 15, 2019 at 8:54 PM #278

    lakeroadster

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    Yowza that cranberry looks plum crazy to me! :rolleyes:

    Seriously though, don't set the bar so high, you're messing up the bell curve for the rest of us.
     
  9. Mar 15, 2019 at 9:34 PM #279

    neil_w

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    I'll try to forget I saw that. ;)

    I did want to do something "different" for this one, and the cranberry does seem to have accomplished that goal.

    Thanks, but I am definitely not the bar-setter when it comes to painting (go look up Nathan's builds if you haven't already). There is a lot of ugly brush touch-up work to come on this one.
     
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  10. Mar 16, 2019 at 2:35 AM #280

    BABAR

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    Regarding nose cone.

    Any chance you can precurve the section to fit before you paint it? Only big challenge is getting the backing off without "uncurving" it after you paint it. Maybe stick it on wax paper?
     
  11. Mar 16, 2019 at 1:07 PM #281

    neil_w

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    Good idea in retrospect. At this point, though, I'll just hope for the best. If that decal doesn't work out it's no biggie; it's not critical to the design.

    It would be OK if it bends in other directions during application; the key would be for the paint layer to be approximately the correct shape in its "resting" position. But I'm still hopeful it'll work out the way I've done it.
     
  12. Mar 16, 2019 at 4:47 PM #282

    BABAR

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    One of the cool things about the forum is testing of different techniques. The idea of making paint color decals (monocolor shapes) so you can customize colors opens up a lot of options. One thing I am curious about is how much “leeway” there is on curvatures, assuming you paint it when flat, how much curve can you do after painting where the paint won’t flake? I was expecting paint to be much less flexible than ink.

    Hope it comes out well.
     
  13. Mar 16, 2019 at 6:46 PM #283

    neil_w

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    Here goes!

    Step 1: cut out the desired shape. This was a total freehand operation.
    Nose-shield-1.jpg

    Step 2: Apply Micro-set. There will be no Micro-sol on these decals, since the top side is completely sealed with paint. But Micro-set should be fine. Smells just like vinegar, I wonder if that's all it is...
    Nose-shield-2.jpg

    Step 3: get it soaking:Behaves like any other decal, initially curls up but eventually I'm able to settle it down in the water.
    Nose-shield-3.jpg

    Step 4: Place on nose. It was "fun" trying to get the placement just right here. And..... up come the edges!
    Nose-shield-4.jpg

    Step 5: Apply even simultaneous pressure to the two edges, without moving the decal. Using a symmetrical two-finger grip was the only way I could get this to work. Keep it there until the decal stays put when removing your fingers.
    Nose-shield-5.jpg

    Finished result:
    Nose-shield-6.jpg

    Final verdict: this technique is a winner. I'm sure there is a practical minimum radius that will work (especially for the metallic paint), but for decent-sized stuff it seems great. You can definitely do things that would otherwise be very hard to do with masks.

    Thank you @hcmbanjo for showing this on your blog, I would never have thought of doing it myself!
     
  14. Mar 18, 2019 at 1:05 AM #284

    neil_w

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    More silver work. I felt comfortable putting these on before doing additional painting because I believe these will be underneath a plastic bag, not in a spot where there will be tape.

    First I cut out the pieces by marking the back side and cutting from the back with a knife and straightedge:
    Chevrons-1.jpg

    Then on they went, same process as before. Definitely required some coaxing in some places to stay down, but eventually they did. Despite significant effort to get them symmetrical and straight and even, they are most definitely not, although not noticeable unless you really study.

    I *think* I like the way they look, but if nothing else they do match the OR render. :)
    Chevrons-2.jpg
     
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  15. Mar 18, 2019 at 2:59 PM #285

    Nytrunner

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    Really nice

    Remember, the rocket isn't supposed to be sitting still long enough to be measured!
     
  16. Mar 18, 2019 at 3:06 PM #286

    neil_w

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    In theory. :). In reality that’s how my rockets spend most of their time, sitting for me to stare at.

    One good thing I’ve discovered: not long after a build is finished, I completely stop caring about imperfections like this. Like the hole I poked in the side of the IRIS-T: big trauma at the time, now a total lack of concern when I look at it. Interesting psychology, don’t know why it is but I am thankful for it.
     
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  17. Mar 18, 2019 at 3:13 PM #287

    lakeroadster

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    Symmetry is over rated... :confused:

    Thanks for walking us through this technique Neil. Alcubierre is quite the looker.

    Understood. You're a scratch builder... once it's done the focus is on the next one.
     
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  18. Mar 19, 2019 at 2:00 AM #288

    BABAR

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    This ship is modeled to Travel at relativistic speeds, and according to Einstein, space is curved.

    Who is to say they aren’t symmetrical?
     
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  19. Mar 19, 2019 at 12:09 PM #289

    shanejohnson2002

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    I'd say they're relatively symmetrical...
     
  20. Mar 19, 2019 at 12:33 PM #290

    JJSR

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    Beautiful work! As always Neil,,

    IDK though, think you should of looked at what I had in the box

    20190319_083225.jpg

    Just saying,,,,:)
     

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