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  1. #1
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    14th July 2015
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    Accur8 Indigo Ragnarok Orbital Interceptor Build Thread

    Greetings. This is a build of the Accur8 (aka John Pursley) Indigo Ragnarok Orbital Interceptor. John calls it a "short kit" which basically means it's a kitbash, in this case of the Estes Cosmic Interceptor. Here is what the finished model is supposed to look like:


    I say "supposed to" because I can already tell you mine ain't gonna be perfect. But it'll still be cool.

    The design is originally inspired by this old plastic kit from 1959:


    That kit was updated and reissued in 1976 as the Ragnarok Orbital Interceptor:


    I've been sitting on this build for quite a while, waiting until I had gotten far enough into it to ensure that the build thread wouldn't take forever. I think I've waited long enough.

    Next up: background

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    Last edited by neil_w; 24th January 2018 at 03:33 PM.

  2. #2
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    Background

    Here is some background on this build. Feel free to skip this crap if you want.

    Back when I was first thinking about becoming a BAR, I ran across some pictures of the Accur8 Twilight Interceptor, and was sort of dumbfounded that such a thing was possible. I vowed that at some point I would have to try doing a skinned rocket. My ideal opportunity came when the Trajector and the Cosmic Interceptor were both put on clearance from Estes, *and* John had a 2 for 1 skin sale. So I figured it was time. I hemmed and hawed a bit (those who have read any of my threads will no doubt be shocked to hear that) but finally pulled the trigger and ordered the skins... and then both the Trajector and the Cosmic Interceptor went out of stock at Estes before I ordered them.

    Fortunately, the Trajector returned, but the Cosmic Interceptor did not. I wanted to combine the order, but didn't want to wait and then have the Trajector go away permanently (as it turned out I needn't have worried, but I didn't know this at the time). So eventually I just ordered the Trajector and assorted other things to get my free shipping, and then John was kind enough to sell me a spare Cosmic Interceptor kit he had at a very reasonable price. So I had my kits and my skins ordered. This was January of 2017.

    The plan was to use the Trajector, being a simple 3FNC, as a practice run for the Ragnarok (which is what i'll call it from now on, because the whole name is too much to type every time). I would learn how to work with the skins so I'd be, if not an expert, at least *competent* when building the Ragnarok.

    Oh, one other thing: I thought the Accur8 builds would be great for the winter because skins! No paint! Seemed like a perfect setup. I was psyched.


  3. #3
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    Last bit of introduction

    When my skins and kits arrived I was excited to check it all out. The Ragnarok package consisted of 2 sheets of instructions, 2 sheets of fin and other templates, and 6 or 7 sheets of skins. The skin prints look to be very high quality. I am very annoyed that it didn't occur to me to make high-quality scans of the skin sheets before I attacked them; coulda made a killer OR model out of this. Oh well.

    Here's what a typical sheet looks like (click for larger):
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    In addition to the assorted skin pieces on this sheet, there are some instructions squirreled away into the open spaces. This is the main thing I'd change about the way these skins are designed: the same instructions appear in multiple different places, somewhat randomly scattered among the various sheets. For this kit, as mentioned, there are two separate sheets of instructions as well. These two sheets have much of the same info twice, except one sheet has smaller print and therefore room for a couple of very useful figures. All well and good except for one thing: the instructions are not exactly the same in all places. In most cases the differences are minor or even insignificant, but it's disconcerting not knowing which instructions to treat as canonical. I guess the bottom line is to read *all* the instructions and sort out your various questions before you start.

    As for the how the build works, I rather quickly noticed that one of my base assumptions about these skins was exceedingly wrong: this is not a no-paint build, *at all*. In fact there's lots of painting and finishing to be done. The difference from normal is that nearly all of the finishing is done before assembly. So, after being bummed about it for a while, I decided that I would just spend the spring and summer doing very leisurely fabrication and finishing of all the various parts, and then come wintertime I'd be ready to skin and assemble indoors.

    Next post starts the actual build.
    Last edited by neil_w; 3rd January 2018 at 03:34 AM.

  4. #4
    Join Date
    29th September 2014
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    Subscribed! I’ve built one of these as a practice run for a pair of Interceptors “short kits” skins customized for my boys. The interceptors have yet to be build, but the Ragnarok turned out pretty well. It’s had one flight. Unfortunately, the chute failed to open as it remained wrapped around in the nonexistent protector.... my error in the setup. It landed with the vertical stabilizer down. It snapped off cleanly in 2 pieces. I think it can be re-attached with some CA.

    Good luck on your build. I found it to be pretty fun.

    I have to also credit John for his great support when I did have a question or two.


    Sent from my iPhone using Rocketry Forum
    Jack
    NAR 41185 TRA 01260

  5. #5
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    Quote Originally Posted by jpoehlman View Post
    Subscribed! I’ve built one of these as a practice run for a pair of Interceptors “short kits” skins customized for my boys.
    Excellent! As we move along I'll be interested to hear how your experience compared to mine.
    I have to also credit John for his great support when I did have a question or two.
    Absolutely true, he is very generous with his support via email. However, I do think he would do his customers *and* himself a service by putting most of that information up in a FAQ on his website. I have no doubt that most or all of the questions I've sent him are the same ones he's answered over and over.

  6. #6
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    First steps

    Step 1: protect the skins.

    A light clearcoat just to keep them safe during handling. I used Krylon UV resistant gloss; afterwards, John told me that stuff has fairly hot solvents and could deform the skin vinyl. Fortunately I applied it light enough that I did not have a problem. While applying Future to my Trajector, though, I did experience a bit of running of the ink in a few spots, so it's possible I went a little *too* light....

    Step 2: cut some wood.
    John said you could use either 1/8" basswood or hard balsa for the fins. I went with basswood, thinking that it would be easier to seal and finish, what with its tighter grain. Also John definitely seemed to prefer it, so I went with it. The fins are laid out on a single 4"x36" sheet that is sort of a masterpiece of jigsaw-puzzling:
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    Apparently my rendition was somewhat less than masterful, though, because I ran out of room for the final fin:
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    So I got another sheet, and now I have plenty of spare 1/8" basswood. I would have needed the second sheet anyway, because one of the fins was not up to par and needed to be recut.

    The horizontal stabilizer assembly is nifty, consisting of two fins and two shaped pieces of wood dowel:
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    The wings, too large for the 4" sheet of basswood, needed to be assembled from two parts each:
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    I did a *lot* of careful sanding with the sandpaper on the bench to make sure the whole root edge of each wing was as flat as even as I could make it. End result was pretty good.

    I went with John's recommendation of rounded leading edges and tapered trailing edges. I learned two things about basswood:
    1) tapered edges are no problem, the pointed edges are not particularly delicate. I would have destroyed them many times over if they were balsa.
    2) basswood takes about 20 times more sanding than balsa to shape it. I was somewhat surprised how long it took me to get all the pieces sanded to shape, but I was in no hurry so I didn't worry about it.

    Here's the finished set of fins, unfinished:
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    So far so good.

  7. #7
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    Looking good!
    Rocket Addict
    More...more...I'm still not satisfied (T. Lehrer)

  8. #8
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    Fin painting and filling

    All the wood fin pieces needed to be filled (sort of) and painted black, for two reasons:
    1) The skins need a good smooth surface to adhere to, and
    2) some edges would be exposed when all finished, and those should be black (actually they'd be better off in a dark blue to match the skins, but no matter)

    Normally I'd paper my fins and apply a coat of filler/primer. However it seemed crazy to paper a bunch of wood that would subsequently be covered by skins. John recommends using Rusto 2x clear gloss as a filler, but only if you sand it within a couple of hours of laying it down, before it becomes rock hard. I couldn't guarantee adhering to that timing, so decided to just try a very heavy (!) coat of Rusto filler/primer.

    I learned a couple of things. First, no matter how heavy you lay it down, it still won't perfectly fill the grain. There's a reason why Micromeister recommends many coats of primer for his "primer-only" fill technique. So I still had a bit of grain showing through in some areas. I decide that really isn't a problem since, again, it'll all be covered by skins. Didn't need to be perfect.

    The second thing I learned is that a very heavy coat of Rusto filler/primer is incredibly hard to sand. I've never had much problem with it before, but then I had never laid it on thick like that before. Very tedious.

    When finished, the fins looked... OK, I guess, but certainly far less perfectly filled than I'm accustomed to. Again, I decided it was OK.

    Sorry I somehow failed to take any pics of the primer stage.

    Then onto painting. The regular fins got taped on their edges, while the horizontal stabilizer was taped to a wood square dowel on the protected strip where the vertical stabs would be attached. I thought I was doing a really nice clean job until I noticed frighteningly large drips and runs on the wings. Apparently i held the can too close or moved too slowly. Think I would have mastered that by now.
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    I also realized that the primer sanding process had removed most of the primer from the edges, and so the paint was quite rough there... and those were the bits that might be exposed.

    First I wet-sanded down all the parts to smooth out the various bumps as well as I could. Then I hand-brushed some Testor's gloss black along all the edges. The edges looked OK when finished, the rest looked like a disaster though (click for giant hideousness):
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    I continued to console myself that the ugliness would be hidden under the skins and wouldn't matter; the surface was still more than smooth enough for the vinyl to stick. I still was unsatisfied, though, so I thought I'd take a crack at polishing with auto polishing compound. I bought some Turtle Wax Polishing Compound (maybe not the best choice, but it was a relatively cheap experiment) and went at it. The results were... well, better than nothing but far from what I was hoping. Here's a before (left) and after (right) on one of the fins, it's very hard to tell what's going on in the pic but the short answer is "slightly better in the after".
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    Eventually I just called it done, despite the fact that I had a bunch of fins that at best could be called "blackish" at this point. But I thought the edges seemed "OK", and the other bits would be hidden. Certainly not the high quality I had been hoping for when I started though.

    At this point I adopted the attitude that no matter how crappy a job I do on this, it'll still be an incredibly cool model. That's my story and I'm sticking to it.

    The best thing was: this marked completion of all the stuff I had to get done in the good weather. The rest of the build would be an indoor affair.

  9. #9
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    18th January 2009
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    Near Denver, Colorado
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    Just curious, What parts of the Estes Cosmic Interceptor kit are used for this kitbash?
    I can see the nose cone, main body tube, and motor mount, but what else? If I could get a hold of a nose cone, could the rest of the parts come from my stash?

  10. #10
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    Quote Originally Posted by goose_in_co View Post
    Just curious, What parts of the Estes Cosmic Interceptor kit are used for this kitbash?
    I can see the nose cone, main body tube, and motor mount, but what else?
    It’s 27” of 2” BT (Cosmic Interceptor does this with 2 pieces coupled together), on additional piece of BT (about 7” long) for the scoop, the nose cone and the motor mount. And the launch lug and parachute etc.

    I *think* that’s it.

    [edit] Nope, two more things: the cardstock vanes that go at the back of the motor mount, and the yellow spacer tube used in building the motor mount. Both could probably be improvised with other stuff.
    Last edited by neil_w; 7th January 2018 at 11:18 PM.

  11. #11
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    Let's skin the tube

    What I learned building my Trajector was that skinning the body tube is the most instantly satisfying step of the whole build. For those who haven't worked with Accur8 skins before, here's how tube skinning works. I'm following John's instructions pretty closely here; the method is pretty highly refined and works extremely well.

    After the skin is cut out, a narrow strip of the backing material is cut off along the edge that will be adhered first (this is marked on the skin sheets)...
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    ... and then put back where it came from.
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    The wrap is then held around the tube in position. This is the single hardest part (such as it is): getting the skin into the exact correct position and holding it there. Note that this method would need modification if we were wrapping a much larger tube, unless you had huge Dr. J hands. For a 2" tube it works fine.
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    Next, lighten up on the edge that has the cut backing strip, and remove just that piece of backing.
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    Stick the edge of the skin down onto the body tube, taking cure during the whole process to keep the skin in that correct position you so carefully found earlier.
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    Now the position of the skin is basically set, all that remains is to stick it on. Lift the edge of the remaining piece of backing and hook it around the body tube. Hard to describe, hopefully the picture shows it:
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    Then simply work your hands around the wrap, starting from the part that is already stuck down. The backing will push away effortlessly as you go, until the final edge of the wrap comes back to join the original. John provides a narrow strip of overlap, which is good because the skin sticks best to itself (more on this later), and therefore this gives a nice secure edge that won't lift. It also ensures that there's no unsightly gap between the two edges.

    Final alignment of the edges reveals how accurately you positioned the skin in the 3rd step. I give myself A- here. I did slightly better on the Trajector, but this is fine.
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    Three body skin pieces complete the job for this rocket. Here's the finished result. There's still lots more work to do on this, but this feels like a nice accomplishment. The whole process literally only takes a few minutes.
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  12. #12
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    Quote Originally Posted by neil_w View Post
    What I learned building my Trajector was that skinning the body tube is the most instantly satisfying step of the whole build....

    There's still lots more work to do on this, but this feels like a nice accomplishment. The whole process literally only takes a few minutes.
    Agreed - the simplest part, but you get the most covered at once and really start to appreciate the beauty of the wrap.
    Rocket Addict
    More...more...I'm still not satisfied (T. Lehrer)

  13. #13
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    Good build thread. I have wanted to see a build thread on this rocket since I saw these skins on Johns site.
    By the way, John has his skins on discount at his site if anyone is interested.
    Go DAWGS!

  14. #14
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    More body tube work

    The rear end of the BT needs a "sausage cut". The skin shows where to make the cut:
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    I was a little nervous about needing to freehand a bit cut like this while the skins were on... my blade tends to wander off sometimes. I tried to do it as carefully as I could, taking about 4 passes to get through the tube and skin. I did OK, but the edge was still pretty rough, and a bit of skin hung out over the edge. Dunno if you can see it in this picture, but it was the best I could do (click for the larger version to have any chance of seeing anything here; that applies to most of the following pictures).
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    Next I had to clean it up. I CA'ed around the edge, and also along inside near the edge. In addition to hardening it up for sanding, it also served to seal the edge of the skin down:
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    Then I sanded as carefully as I could. Part of what I had to do was sand off the bit of the skin flapping over the edges (we're talking about 1 mm here), so I had to sand with a block on the outside. The end result was good, but as expected I ended up with a considerable bit of white skin-edge showing:
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    I am very happy that the "background" color of this build is black. I ran a black Sharpie carefully around the edge, eliminating all the bits of white at the edge. Only a couple of times did I drift onto the exterior skin; like I said earlier, this build is destined to be "good enough", and not nearly perfect.
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    Here's a side view of the edge. Compare to the 2nd pic near the top and you'll see (?) the difference. The end result is not perfectly smooth but it's absolutely good enough.
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    On the forward end of the tube, I noticed that the skin did not come all the way to the edge:
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    I'm not sure why that came out like that, but either way I'll fix it later, either by trimming off that bit of BT, or by applying a bit of extra skin (not sure if I'll have a piece of the appropriate size yet). Or I could just Sharpie it.

    That mostly takes care of the BT. But there's still a bit more to come...

  15. #15
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    A few more bits of body tube work

    Note that I'm documenting the build in a different order than I've actually done it, to make it a bit more organized.

    So, the body tube is not quite finished. First, we must remove all the bits of vinyl where stuff will be glued to the body. I did an *extremely* careful job on this and was very happy with my results. Here's the spot where the vertical stabilizer gets mounted after I removed the strip:
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    The next day I went to check on things and was greeted by this:
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    Basically, *every* edge was lifting where I had cut it. This has become a theme of the build for me: this particular batch of vinyl is insufficiently sticky and/or flexible, and virtually every edge that is attempting to adhere to a curved surface will lift up. The exceptions are the places where the skin adheres to itself (such as where the body wraps overlap at the edges.) John told me back when I bought this that he has experimented with different vinyls and briefly used a version that had a less aggressive adhesive. I believe that my vinyl is from this batch, although that's up for some debate based on recent discussions with John. In any case I would suspect that newly issued skins will not have this problem, but that doesn't help me right now.

    I had already been dealing with this issue (a lot) when skinning the fins, with varying success (like I said, I'm posting in a different order than I'm building), but I have to admit feeling a bit of despair when seeing the body tube pieces lifting up like that. Although it is possible to glue the edges down (I'll cover this later), it is hard to do without making a mess, and I do not enjoy it. And so I took a deep breath, stepped away for a bit, and thought about it. Ultimately I realized that I *should* be able to deal with this in a reasonable way when gluing on the fins. So I decided not to do anything about these at the moment, despite how ugly they look right now.

    Lastly, the inside of the sausage cut is painted black. Instead of my usual Testor's enamel, I tried some Tamiya gloss black acrylic. Actually I should probably have used flat for this but no biggie. I really like the Tamiya paint; it dries fast and levels extremely well. Although it stinks while painting and drying, the odor dissipates much quicker than the Testor's enamel and since it cleans up with water there's no added stink of the thinner. With no primer, two brushed-on coats provided excellent coverage. Thumbs up.
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    After the motor mount is installed there will be a bit more work to do here, but it'll be a while before I get to that.

    Next up: a few days in Florida, and then I'll start in on the fins when I return.
    Last edited by neil_w; 10th January 2018 at 06:10 PM.

  16. #16
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    25th February 2009
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    Enjoying this build thread. I've been curious about the Accur8 skins. Thanks for posting.

  17. #17
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    That's a bummer, have you contacted John, he might replace the skins rather than try to work with bad adhesive, I think you may have problems on the cone if the stickiness is poor....

    Frank

  18. #18
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    Quote Originally Posted by burkefj View Post
    That's a bummer, have you contacted John, he might replace the skins rather than try to work with bad adhesive, I think you may have problems on the cone if the stickiness is poor....
    I have but I should probably contact him again.

    You're right that the nose cone is going to be an issue. I had problems with edges lifting on the nose cone on my Trajector but was able to work through various fixes and came out with a good result, but for various reasons I might not have as good luck with it here. In any case that is why I'm leaving the nose cone until the end.

    Let me emphasize that the build continues to move forward despite the problems (it's about 3/4 built at this point) and it looks hella cool on my bench.

  19. #19
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  20. #20
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    Quote Originally Posted by neil_w View Post
    Step 1: protect the skins.

    ... I learned two things about basswood:
    1) tapered edges are no problem, the pointed edges are not particularly delicate. I would have destroyed them many times over if they were balsa.
    2) basswood takes about 20 times more sanding than balsa to shape it. I was somewhat surprised how long it took me to get all the pieces sanded to shape, but I was in no hurry so I didn't worry about it.

    Here's the finished set of fins, unfinished:
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    So far so good.
    Actually, basswood sands quite quickly...if you don't think of it as "hard balsa." Rule #1: Use a high quality (it makes a difference) very coarse OPEN GRIT sandpaper. Bass has a strange clingy, packy (technical terms) sanding dust that quickly reduces the cutting speed of sandpaper. Open grit grit simply cuts faster and works better with bass. Rule #2: Sand ALONG the grain. Yup, sounds counter intuitive but bass sands faster when you sand parallel to the grain. You should be able to sand everything for the RAG in 30 minute or less.

    John Pursley

  21. #21
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    11th February 2011
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    Repeated Ragnarok Instructions

    Quote Originally Posted by neil_w View Post
    ... the main thing I'd change about the way these skins are designed: the same instructions appear in multiple different places, somewhat randomly scattered among the various sheets.
    Even though many elements of the instructions, cautions and whatever are repeated, often more than once you would be surprised how many emails I get with questions like "should I put a coat of clear on my skins before I start?" Rather than be a smart-a** and respond with "Have you read the instructions on any of the sheets?" (this particular question is answered on almost every single sheet in the kits...) Igenerally just give a straight answer that is "YES." So, even though it's repeated, folks don't see it. I hate to see space go wasted so pretty much every nook and cranny on the skin sheets have some kind of information applicable to the skin kit. The instructions have evolved over time for almost all my kits and frequently, as a result of correspondence with a modeler having a particular issue or problem I frequently immediately go to the graphics file for that kit and put the change (or something related) right on the skins so the next time it's printed you get the latest and greatest <sic>.

    I'm not much of one to skimp on replies. I realize the most STUPID question is the one that is not asked...so I appreciate those wo DO take the time to ask! ...And I try to respect that by providing thorough answers.

    John Pursley

  22. #22
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    Status update: I discussed this with John over email. He said that just printing new nose cone skins would not be a good idea since there's low chance of the new ones being a very close match to the old ones, plus the design has changed a bit. He graciously offered me a complete new set, but this build is way past the point where I can start fresh, so I decided to just finish up with what I have. I know what I'm dealing with, and my techniques for deal with unruly skin edges keep getting more refined, so I will make it work.

    I've learned a bit about the behavior of these skins (which may or may not be exactly the same as what John is shipping right now; still not 100% clear to me). Some of this was mentioned explicitly by John in emails during the purchase process, but having a lot of hands-on experience now makes my understanding much more nuanced. Here's my summary so far:

    A) Surfaces these skins like to adhere to, from best to worst:
    1) Other skin. Example would be the little overlap strips on the body tube wraps. This generally keeps the wraps in place pretty solidly.
    2) Finished surfaces. This is one reason why you must seal and paint all wood pieces.
    3) Unfinished surfaces. A fine example would be the body tube, where the cut-outs for fin attachment are made.

    B) Also very important: these skins like to be flat (this characteristic is possibly enhanced by the clear-coat on top which adds a bit, however tiny, of additional stiffness). They will certainly conform to curves, but *all* the lifting I have seen involves curved skin trying to straighten out. In this respect it is very different from the stuff that Stickershock sells. Their vinyl is thicker but much softer and more compliant, and also reacts much better to softening with a hair dryer.

    By taking into account A and B you can anticipate and plan how to deal with most of the problems I've encountered.

    Proper build updates shall resume shortly.

  23. #23
    Join Date
    14th July 2015
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    Randolph, NJ
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    Motor mount

    The Cosmic Interceptor motor mount is a bit more involved than the usual, mostly because of the vanes and tail ring. John was very clever the way he adapted it to this model. Let's do it.

    On the Cosmic, the vanes extend beyond the diameter of the main BT. Here, the motor mount will be inside the sausage cut, so no room for that extra extension. And so the eight vanes are trimmed down as follows:
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    Next, the mount is assembled as per the first 16 steps (!) of the instructions in the Cosmic Interceptor (steps 17 and 18 involve installation of the tail ring, but that goes unused here.)
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    The motor mount tube is not a standard BT50, it is thick-walled and strong. The centering rings, on the other hand, are simple cardstock. While they presumably work fine for the motor mount, I'm certainly not going to anchor my Kevlar to them. I will pursue an alternate solution later. Usually I trim the motor hook, but on this one I left it intact. You'll see why below.

    Credit to John Boren for a very clever and well-thought out assembly sequence for the motor mount.

    The rear end of the mount is painted black; again I brushed on two coats of my Tamiya gloss black. On it's own this looks kind of crappy, but it's not a very visible part of the finished model and will be fine. Flat paint would have shown less of the surface imperfections.
    Click image for larger version. 

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    The finished mount goes into the sausage hole and butts up against the coupler that joins the two body tubes. This makes it easy to place the mount: just push it in until it stops. The fit is tight; after my first test-fitting I was unable to pull it out by hand, and had to grab the end of the tube with needle-nosed pliers and yank it out. I was very relieved it came out at all, and without damage. Since this had "seize-up" written all over it, glued in the mount with 30 minute epoxy. Here it is, installed:
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    Note that I oriented the engine hook on the "inside". There is enough space to simply push the hook away from you, against the inside of the sausage cut, and remove the engine. Done this way, the hook is essentially invisible, and the extra finger grab on the end makes it easy to use.

    One final step remains: coat the inside of the sausage hole with a thin layer of epoxy, to protect it mostly from the burning of the delay grain. I'll get to that later. Next we'll start on the fins.

  24. #24
    Join Date
    14th July 2015
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    Here’s the inside of the sausage cut after applying a thin layer of epoxy.
    Click image for larger version. 

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    I seem to have forgotten that my epoxy (Great Planes 30 minute) does not dry clear. I will decide later whether to put another coat of black paint over this, or just leave it. If nothing else it does definitely seem to be well protected.

  25. #25
    Join Date
    14th July 2015
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    Randolph, NJ
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    Nose cone

    This build thread is getting much less interest than I expected, but I'm having fun writing it anyway. I had previously intended to document the fin skinning and assembly now, but I've changed my mind and will do the nose cone, which is the most challenging skin job. I was surprised how big these nose cones are, about 11" long not including the shoulder.

    Anyway: first we need to prep the nose cone. The gun ports on the bottom need to be filled in, and all the various channels (other than one) may optionally be filled. I figured I'd fill them all, why not? Well the reason why not turns out to be that it's a lot of work for not much benefit. I prepped my Trajector nose cone first, filling in all the channels (again, except the special one). After filling, it looked like this:
    Click image for larger version. 

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    I then decided not to fill the channels on the Cosmic nose cone just to save the effort. Then I swapped the two, so for this build I'm using the fully filled Trajector nose cone pictured above.

    Filler/primer and black gloss paint followed. My paint job turned out to be not nearly as smooth as I thought while I was painting. After seeing how challenging skinning the nose was on the Trajector, I knew I didn't want a bumpy paint job to cause me misery on this one, so I gave it a good wet-sanding with 1500 grit and then applied a coat of Future to give the vinyl a nice glossy surface to grip. The nose cone was now looking pretty darned good and ready to skin:
    Click image for larger version. 

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    The first skin piece is the hardest, as it must conform to the area around the cockpit. Having struggled a bit with this on the Trajector, I figured I could do better the second time. First I decided to pre-curl it, like I'd do with a transition, thinking maybe it would help it hold its shape better:
    Click image for larger version. 

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    This seemed like a good idea but I don't think it made the slightest difference. Here it is after application:
    Click image for larger version. 

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    I didn't get a particularly good alignment of the two ends of the wrap (call-out on the right), I give myself a B- for this. In the middle you can see a spot where I slipped with the Sharpie when I was blackening the edges of the skin. Turns out that will be covered later anyway, so it's a don't-care.

    The light-colored pieces near the cockpit are carefully cut off, leaving this:
    Click image for larger version. 

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    Next up comes the tip piece and the "glare shield" that goes on top, mostly covering the top seam:
    Click image for larger version. 

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    The glare shield didn't want to stay all the way down, so I sealed down the edges with Scotch Satin tape. John originally told me that clear tape is one way to affix skin edges, and to my surprise it worked really well on the Trajector so I was ready with it this time. It disappears against the skin almost completely. This close-up of the glare shield has a piece of tape on both sides holding down the edges, can you see them?
    Click image for larger version. 

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    Next the rear wrap goes on...
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    ...and now I'm ready for the cockpit windows, which gave me a lot of trouble on the Trajector. One improvement here is that due to the black background, the front cockpit windows are done as a single piece that wraps over the top, rather than two separate pieces as on the Trajector. That means fewer edges to lift. I applied the pieces and the main change I made this time was that I burnished the living crap out of the edges with the curved back of a Sharpie (I've been doing that to all the edges on the nose cone). Knock on wood, the cockpit windows have stayed put so far. I'll keep an eye on them.

    Here's the finished nose cone. All told, there are 8 pieces of skin and (if I counted correctly) 6 pieces of corrective tape. I screwed up a bit here and there, but the end result is a handsome finished cone:


    The nose cone skinning process is very carefully thought out. I would be interested to know how long it took John to settle on the whole sequence, and the exact shape of all the pieces. It must have taken many iterations.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  26. #26
    Join Date
    5th December 2013
    Location
    MD
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    7,401
    Very interesting. Way outside my realm of experience. Not that I have a realm....

    John S. ---- NAR #96911 ---- TRA #15253 ---- MDRA #067 ---- BARC #028
    L1, 3/15/14: Aerotech Sumo, CTI H133BS
    L2, 6/21/14: Giant Leap Vertical Assault, CTI J240RL
    L3, 3/12/16: MAC Performance Radial Flyer, CTI M1101WH
    Altitude: 13,028', L3 flight; Speed: Mach ???, L3 flight

  27. #27
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    14th July 2015
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    Randolph, NJ
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    Quote Originally Posted by Bat-mite View Post
    Very interesting. Way outside my realm of experience. Not that I have a realm....
    After doing a couple (well, 1 3/4 so far) of these skinned rockets, I'm pretty sure I would recommend to everyone to try one. It's a completely different build experience from the normal, and the end result is likewise very different and very cool.

    Estes still has the Trajector for $15.99... it's mighty cool with the NASA skin.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  28. #28
    Join Date
    4th October 2014
    Posts
    901
    Quote Originally Posted by neil_w View Post
    ... I will decide later whether to put another coat of black paint over this, or just leave it. If nothing else it does definitely seem to be well protected.
    https://www.homedepot.com/p/Rust-Ole...1169/203161184

  29. #29
    Join Date
    14th July 2015
    Location
    Randolph, NJ
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    Hmm, that is a thought, if I am willing to buy a can just for this one application (probably not ) I could decant it and brush it on. Will consider. Wish I had some leftover from when I painted my fireplace grate, but I pretty much used up the whole can....

  30. #30
    Join Date
    20th January 2009
    Location
    Johnson City, NY
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    2,099
    Quote Originally Posted by neil_w View Post
    This build thread is getting much less interest than I expected, but I'm having fun writing it anyway.
    Not really "less interest". I've been watching and following each installment. I plan on getting one soon. Looks great.
    So fat I've done the Twilight Interceptor and NASA Trajector.

    Rocket Addict
    More...more...I'm still not satisfied (T. Lehrer)

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