Build thread: Sport-scale IRIS-T missile, 1:3.8-ish

Discussion in 'Scratch Built' started by neil_w, Mar 11, 2018.

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  1. Jun 27, 2018 #91

    Nytrunner

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    Recoat in 10-15 minute intervals, but after an hour must leave 48 hrs before Next coat or masking.

    That Is Not A Suggestion
     
  2. Jun 27, 2018 #92

    neil_w

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    Thank you sir. At least you got in before the nose cone. :)

    Agreed, this is standard procedure for all the Rusto 2x paints that I use (although I believe this will be the first "Ultra Matte" variety I've tried). Actually I don't think I've ever waited less than 4 days before next coat, more typically a week. Meanwhile, the sniff test is a fantasy for this stuff; it still has noticeable smell for... weeks? Months? Eons?
     
  3. Jun 27, 2018 #93

    Nytrunner

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    Oops, I was trying to quote Bruiser. New forum tools are fine, just take some getting used to.

    Just felt he needed a warning if he wanted to try it. I know you've used this stuff for awhile.
     
  4. Jun 27, 2018 #94

    neil_w

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    Oh, I thought he was commenting on the particular color. :oops:

    (do not love the new smiley collection)
     
  5. Jun 29, 2018 #95

    neil_w

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    It occurred to me that I need to get going on the decals, because I'm going to need the first of them sooner rather than later. Since my nose cone strategy has shifted to representing a functioning live missile (rather than a display model), I needed to shift the paint scheme accordingly. Although the paint scheme continues to be an amalgam of different ones I've seen in pictures, the one thing that absolutely needed to change was the stripes: previously I had blue for display, now I need yellow and brown for "live and armed". The rear stripe location moves up a bit too. And I end up with this:
    Screen Shot 2018-06-28 at 9.50.48 PM.png
    It is possible, or even likely, that the IRIS-T logo is almost exclusively reserved for display models, but I like it too much to leave it off. Also uncertain are several details such as the warning box between the wings, the CG marker at the front of the wings, and the forward-facing arrows on the control fins (hard to see in the above picture). I might remove one or two of these details to keep the whole thing from looking just a bit too busy. But the above image is pretty darn close to what I'll be aiming for. Oh, plus some rivets. Lots of rivets. That I am not particularly looking forward to.

    I have never printed my own decals before, this should be "fun". I'll be using the Bare Metal Foil clear-backed decal paper sold by Erockets. Hopefully it'll work out.
     
  6. Jun 29, 2018 #96

    Bruiser

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    Might not be scale with the mix of decals but I think the pic looks great. Did you get the new paint on?

    JMO,
    -Bob
     
  7. Jun 29, 2018 #97

    neil_w

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    It certainly is not scale. On all the pictures I've seen of this missile, every one has a unique paint job. So now there will be one more. :)

    Soon. You'll hear about it here, I promise. ;)
     
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  8. Jul 1, 2018 #98

    neil_w

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    And now, at long last, I can answer "yes".

    First I put on a couple light coats of white primer:
    Photo Jul 01, 10 49 31 AM.jpg

    Then three coats of Rusto 2x Perfect Gray:
    Photo Jul 01, 11 19 36 AM.jpg

    Well yeah, those two picts look almost exactly the same, due to the imprecision of the photography. This is an occasion where a different colored primer would have been helpful. The Perfect Gray is a pretty light gray, but it is definitely gray. It's probably a shade or two lighter than scale, but it's definitely a better color than the old dark gray was.

    Even better, it *seems* to be a decent quality coat of paint, also much better than the previous. Unless it crinkles up while curing, or I discover some other horrible flaw(s) when it's dry enough to inspect it closely, I'm calling this a success.

    The paint seems to have more of a sheen to it than I would have expected for a matte paint. I am actually wondering if it's smooth enough to take decals directly, or if I still need to apply a coat of gloss first. Anyone tried putting decals directly on Rusto 2x Ultra Matte? I will have to experiment.
     
  9. Jul 2, 2018 #99

    Bruiser

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    That's great news! It looks like the same gray in the pic three replies before this.

    -Bob
     
  10. Jul 2, 2018 #100

    neil_w

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    It's a bit lighter, but that should be better for the inkjet-printed decals. We'll see soon enough! (I hope) I'm most pleased that it seems to be a much better paint job than before; everything seems pretty smooth. I'm sure there will be imperfections as always, but it won't be a piece of garbage like my last attempt...
     
  11. Jul 2, 2018 #101

    Charles_McG

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    I had serious trouble with simple Rusto 2X matte on my Saturn V decals. But it was -really- matte. Almost gritty.
     
  12. Jul 2, 2018 #102

    neil_w

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    That's what I was expecting, but instead I got this:
    ultramatte.jpg

    I'm gonna print my decals tonight, clear coat them tomorrow, and hopefully start experimenting next week.
     
  13. Jul 2, 2018 #103

    Nytrunner

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    The logo looks good on it whether it's dud or live. Helps educate people.

    Speaking of nose.....
     
  14. Jul 2, 2018 #104

    neil_w

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    You cruel taskmaster.

    Working on it! Have to apply the decal to the base before I can continue. Which means I have to make some decal decisions, print them and clear coat them first. Making steady progress.
     
  15. Jul 10, 2018 #105

    neil_w

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    OK, I have brought the rocket in from the shed, taken a bunch of careful, scientific measurements, and can say with confidence that the new paint job is a zillion point zero zero times better than the old one. I am relieved; it was worth all the effort sanding it down.
    Newpaint-2.jpg
    Newpaint-1.jpg
    In fact, it looks pretty great. There are only a couple of small defects and they are insignificant. I am excited to move forward at last.

    Actually, I *have* been moving forward, but haven't been able to show anything new for a while. Lots of sequential drying intervals of various types. Will have something interesting to show... I dunno, maybe by the end of the week if all goes well.
     
  16. Jul 12, 2018 #106

    neil_w

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    OK, let's get to the nose cone. Should be done in about 3 parts. Here's part one.

    From the beginning, my goal is to recreate this in some reasonable fashion:
    nose1-0.png

    Strategy: start with a balsa nose cone, chop off the end, and then figure out some way to do all the other stuff.

    I calculated that I want a nose cone that would be about 1" in diameter about 1.5" from the base of the cone. Erockets had a 3.1" ogive cone that seemed to fit the bill.

    First I CAed it, mainly to protect it from all the handling it was about to receive.
    Nose1-4.jpg

    Then I cut a 1" hole in a piece of cardstock and used it to mark the cut line.
    Nose1-5.jpg
    I cut it very conservatively, leaving the final exact shape to sandpaper, where I could do it very slowly and carefully.
    Nose1-6.jpg

    (cutting and sanding the CAed cone was interesting; it was like it had a crunchy candy coating)

    Next up: the clear dome. I needed clear plastic, reasonably strong (but not excessively so; this is only flying on Cs and Ds), a bit over 1" in diameter since I want slightly less than a full hemisphere to match up with the 1" end of the nose cone. As previously documented, I found the perfect item at a Dollar Store after about a hundred billion hours of searching in too many stores to count. Worth it! :rolleyes:
    Nose1-1.jpg Nose1-2.jpg

    I cut off the dome with a razor and sanded it down to size, then coated it with some Future for protection, which may or may not turn out to be a good idea. End result: one lovely oversized contact lens:
    Nose1-3.jpg

    I sanded everything to matched sizes and came up with this:
    Nose1-7.jpg

    So far so good. Next I applied thinned CWF and a coat of filler/primer, and now the cone was nice and smooth. I drilled out an oversized hole in the base for a future eyelet that will have to hold some washers for weight. For this task I put the drill bits (successively larger sizes) in a vise to the desired depth, and turned the nose cone by hand onto the bits. That worked fantastically. Will get back to the eyelet and washers later (still need to figure out the desired amount of weight).
    Nose1-8.jpg

    Finally, I applied a coat of Perfect Gray to the nose, and the first phase is complete.
    Nose1-9.jpg
     
  17. Jul 12, 2018 #107

    Bruiser

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    Looks very cool too me. So are you going to insert a short piece of dowel into the balsa for the screw eye?

    Can't wait to see this all together with the decals and all :). It'll be awesome!

    Bob
     
  18. Jul 12, 2018 #108

    neil_w

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    Current plan is to fill the hole with epoxy and stick the screw-eye in. Should be very strong. We'll see how that goes later...
     
  19. Jul 12, 2018 #109

    Bruiser

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    Epoxy should work well to hold the screw eye in also. This is shaping up great!

    -Bob
     
  20. Jul 13, 2018 #110

    neil_w

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    Here's part 2 of the nose cone: the camera and gimbal.

    I actually lied in the previous post where I said I had intended to reproduce that nose cone right from the beginning. In fact, I originally was targeting one of the noses on one of the non-functional display units, which look like this:
    nose2-demo.jpg

    When I started to build it, though, I was unhappy with my results, and also since I changed the paint scheme from display to fully functional, the nose cone should follow suit. I collected all the pictures I could find of the functional nose, so I could see the camera and gimbal from all angles:
    nose2-collage.jpg

    It was pretty clear the only way I was even going to come close to this was with 3D-printing. So I whipped up a model in Tinkercad that seemed to approximate it pretty well:

    nose2-model.png

    ...and then spent too much money having it printed in black resin (my first SLA print). Here's the finished part, with penny shown for scale:
    Nose2-4.jpg

    Next I gathered up three bottles of Testor's enamel, and some of those super-fine detail brushes, and went to it. The results are good, although in extreme close-ups they do not fare so well:
    Nose2-1.jpg

    That takes care of everything but what I call the "iris" of the eyeball, the greenish ring surrounding the black "pupil". A lot of the pictures show a bit of gradient between greenish and a more pinkish color; I wasn't gonna be able to do that with paint so I printed and made a little (!) transition:
    Nose2-5.jpg

    I don't know if that is "Dr Zooch" small, but for me it was by far the smallest one I've made, and it was tricky. Actually the one shown in the picture is not the one I eventually used; I made another that was a bit more bluish to match the above pictures. Getting it to fit nicely onto the resin part meant making *many* of these, tweaking sizes until it was close enough to sit well (could never get it perfect). Glued it on with some CA and voila:
    Nose2-2.jpg

    I think that is a decent approximation of the real thing. It's the sort of thing that would have been much easier to do at a larger scale. Maybe someone else will try that (ahem).

    It also would have been better if the nose cone were hollowed out, so the assembly would sit "in" the nose rather than on the surface, but that wasn't an option for me.

    That concludes this chapter. The next one will put the whole nose cone together.
     
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  21. Jul 15, 2018 #111

    neil_w

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    Let's finish off that nose cone.

    The top is painted black. I left a blank area in the middle for gluing the camera piece. Originally I tried to leave a bit of blank border for gluing the dome, but I couldn't get it precise enough and it looked bad, so I just painted out to the edge. That's flat black paint, reflecting the light. In real life it is indeed black.
    Nose3-1.jpg

    The camera/gimbal piece from the previous post was then epoxied on top. At some point the decal found its way on as well.
    Nose3-3.jpg

    Speaking of that decal, I put the black line as close to the shoulder as possible, but couldn't get it quite there. I painted the little space below the black line with some Tamiya gloss black (results visible later).
    nose3-decal.JPG

    Gluing the dome on was a pain. I went to first clean it off with some alcohol, and immediately learned that alcohol clouds Future. I was relieved when another two coats of Future cleared the clouding. Even still, the dome was showing some evidence of the handling it had received, but I was not in the mood to make a new one, so on it went. First I made myself a tape "handle":
    Nose3-4.jpg

    Then I applied a thin bead of medium CA with a Q-tip around the edge of the dome, and applied it. And then, a few minutes later, removed it, having found that it just did not stick. So out came the epoxy, which I applied *sparingly* to the edge of the dome. Didn't want any extra glopping out, because I wasn't gonna use alcohol to clean it up.

    It went on pretty well, and the epoxy seems to be holding on pretty strong. In hindsight, I could have poked a few pinholes around the perimeter of the balsa nose, to make some epoxy rivets, but it looks like it won't be necessary. We'll eventually see if it all survives landing, which is always the thing.

    After a flat clear-coat the nose is finished.
    Nose3-6.jpg Nose3-5.jpg

    In the second picture you can see that the black now goes all the way to the shoulder, so when it's inserted into the airframe only a single black line should show. Also, with the flat coat, the clear decal backing *mostly* disappears; you can still see it at some angles, but I chose not to use those here. :)

    I'd say the end results is pretty nifty. Including the search for a suitable dome, I spent more time on this nose cone than on some whole rockets.
     
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  22. Jul 15, 2018 #112

    snrkl

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    Looks awesome Neil!!!
     
  23. Jul 15, 2018 #113

    neil_w

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    Thanks! It looks even better on the rocket, but I'm not showing that until the full reveal at the end. Gotta save something. ;)

    Main rocket decals are in progress, coming out pretty well so far.
     
  24. Jul 15, 2018 #114

    BDB

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    This is awesomeness!!!
     
  25. Jul 15, 2018 #115

    Nytrunner

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    it's going to be difficult to put on the nose cone with "No Support or Handling" beyond that line
     
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  26. Jul 15, 2018 #116

    neil_w

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    You know, you had about a HUNDRED opportunities to warn me about that before now.

    I am now well and truly screwed. Build is over folks, I'm taking my ball and going home. :mad:
     
  27. Jul 15, 2018 #117

    Nytrunner

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    Trying to decipher and investigate those markings was kind of fun
     
  28. Jul 15, 2018 #118

    sooner.boomer

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    Looks pretty sweet. Working with details at that small of a scale can be challanging!
     
  29. Jul 15, 2018 #119

    neil_w

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    Indeed. This would have been a much different project if this missile were fully documented somewhere.

    Although I’m perpetually self-doubting about whether I’ve made the right choices regarding the decal scheme, I think anyone would look at the end result (once I get there) and say the whole thing is a pretty solid sport-scale representation.

    2/3 of the way through the decals it is looking really good. Bolt heads come next, some tricky bits await.
     
  30. Jul 15, 2018 #120

    KevinM

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    I'll echo what was said a long way back - what a great build, I can't believe it took me so long to find this!

    Although it can make for a bunch of extra steps, if you do any more builds with decals like this you may find that the clear parts disappear better (and will certainly adhere better) when put down on a gloss surface instead of a flat one. You're going to over-coat it with flat anyways, right? The tricky part with this is finding military colours in a gloss finish, otherwise you need to paint, gloss-coat, decal, then dull-coat.

    Another thought on the finish for the dome - you may come to appreciate the way a gloss finish on the dome compared with a dull finish on the rest of the model helps to draw attention to all the wonderful work you put there.

    Thanks as well for posting the source on those clear domes. I'm going to have to take a look around and see if I can find something similar for the "XBT cover" on my 1/2 scale TOW.
     

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