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chanstevens

Well-Known Member
With the weather turning [poopy] and scrubbing launch plans, I decided to break open Decim8 #44 and begin what looks to be a significant and challenging build. I had proofed Jim's directions a couple times before it came out so had a pretty good idea what I was in for, but it wasn't until I opened the bag that I really appreciated what I was in for.

First thoughts? Man, that's a lot of body tubes for just one nose cone (ignoring the two itty bitty MMX nose cones in the small parts baggie).

chanstevens

Well-Known Member
Part of the reason there are so many body tubes and so few nose cones would be because the body tubes are mostly scalloped and sliced to fit together. You'll definitely want a fresh blade for this project. I spent the better part of one evening just cutting tubes.

These shots depict a set of parts and an assembled side pod. Cut form BT-50, with a BT-2.5 wedged inside the seam.

I wanted to dry fit everything a couple of times to get my head around the paint scheme, as there's clearly no chance of masking this very well once built. For these pods, as an example, I plan on painting the longer outside halves red metallic, the shorter outside halves purple metallic, the BT-2.5's black metallic, and the inside of the tubes blue metallic. That's just for one relatively small subassembly...

chanstevens

Well-Known Member
The main upper and lower body tubes, naturally, aren't standard coupler joints. Each is scalloped and slotted to mate together halfway overlapping. The exposed ends are covered with a balsa panel, hand cut and trimmed to fit. I'm taking a significant detour from the prescribed approach because I want to paint the upper and lower tubes different colors and felt masking and getting decent coverage in such tight corners would be tricky. If you look inside the ends of the tubes, you'll spot a crescent-shaped bulkhead. That's a reinforcement that rests against the other tube when they slide together. It's supposed to be on the outside before sliding them together, and then once they're together you cut/glue on the balsa cover panel. I needed the panel on before mating the tubes, so had to put that reinforcement bulkhead in there first. Sliding them together is a PITA now, but it will allow for a beautiful paint job.

The lower tube has a BT-20 motor tube that extends out a little over an inch, so obviously you need a ping pong ball for the transition . I've got to clean up those holes a bit, insert a launch lug, trim off the ends and fill in any seams.

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chanstevens

Well-Known Member
Having covered all the tube cutting, slotting, and filling spirals I figured the majority of the work was done. Turns out the fins are no walk in the park either. There are a total of 12 hand-cut fins, just about all of which have at least one curved edge. Heck, two of them even have curved root edges! No pics yet, as I'm prepping them for paint before the wife pulls into the garage and shuts down the "paint booth" for the night.

Let's see--12 fins, 4 get little dowel guns cut and attached to the tips, 2 get little toothpicks wrapped with paper slipped into launch lugs attached to them, and one gets a little section of BT-2.5 (scalloped, of course) attached to a little radar dish. The radar dish is a paper shroud top attached to one of the off-fall pieces of ping pong ball cutouts for the bottom.

Did I mention this was a challenging build?

jflis

Well-Known Member
Kewl

I've been hoping for a Decim8 build thread...

This is gonna be fun!

chanstevens

Well-Known Member
The 3-day weekend proved to be not quite enough time, as life prevents me from the last couple hours of detailing work.

I lied on the fins, by the way--there are only 11. It will seem like about 20 when you're putting them on, though.

Got a lot of paint work done today and started fitting sub-assemblies together. The funky side pods are made from a pair of scalloped BT-50's slipped together with a BT-2.5 inserted in the gap between the lips. I managed to paint half the outside bright red metallic, the other half purple metallic, and things lined up fairly well. I didn't want to mess with painting the insides, as I tend to wind up with heavy runs, so I applied sparkling blue decal stock to the areas that would be exposed. When everything went together, it looked pretty slick, especially in the sunlight when the metallic really sparkles.

chanstevens

Well-Known Member
Time to start building out from the main body tubes. First thing to deal with is that pesky ping pong ball transition. Cut to slide over two different sized body tubes, plus a launch lug inserted to mount flush against the BT-50 and go through the ball. That was a lot of fun .

With the "transition" in place, the first pair of fins (aka main fins) goes on. The fit around the ball was pretty good, but I found a little sanding and trimming was needed. If you build it naked (the model, not the modeler :y, this can easily be handled with a little filler putty, but for pre-painted assembly the seams really need to be minimized. Just about everything was attached by scraping a thin line of paint off, and using 30-minute epoxy. Boy did I mix up a lot of 8-gram kits today.

With the pair of main fins in place, I could then mount the pod sub-assemblies and the outermost pair of fins.

Killing time this evening, I applied a really tiny fillet of white glue to just about every joint using a syringe. The fillets are so small, I didn't even pick up any glue running my finger along the lines, and they'll dry clear.

Still to go--little gun type assemblies on the two outermost fins, 8 weird curved fins that wrap around the ball and then anchor a little slice of BT-60 ring hanging off the aft end, a little antenna dish thingie up topside, and hand painting the dowels on the pod fins, plus decals.

One significant D'oh! moment when I looked at the decals--the header art on this shows a lot of light purple (OK, lavender). I had seen preliminary artwork and decals on this before the kit came out, and gave Jim a little grief over using lavender for a main color. I assumed it was still there, which is why I have a lot of purple metallic on my paint scheme. I noticed on the decal sheet tonight that he's dropped the lavender and gone with a pastel blue for a couple trim decals. There's not enough blue on this to really make that work, so I'll probably wind up leaving off a few decals.

chanstevens

Well-Known Member
By the way, Jim--I know the aft end on this gets a bit crowded, but when I anchored the two main fins on, one of them wound up sitting right on top of the motor hook. Naturally, it was the second one, so trying to reposition it would have my fins not quite at 180 degree orientation. I might be off a little bit on my lines, but I suspect there's just not enough room for a main fin and motor hook in between two of those curved fins. If I were doing it over, I'd probably think about using a wire instead of standard motor hook, or maybe leave out the hook entirely and try tape retention, though getting tape in there around a motor could be a pain, too.

mjennings

Well-Known Member
Beautiful work Chan! I'm gonna have to sit down and really think about this one before I get started on mine.

Gus

Well-Known Member
Chan,

Very, very nice.

Would you mind giving us a list of the paints you're using. Those metallics look great. Really nice idea to use the decal stock, too.

Steve

chanstevens

Well-Known Member
The black and silver are Rustoleum metallics. I'll rummage through the basement later tonight and look up product numbers, but in general the "metallic" paints I use have a glittery sparkle mixed in them as opposed to just a mirror-like shine to them. I especially like the black, and when I used that along with a pearl green on the Alien 8, it was remarkable.

For the colors, though (purple, red, blue, and not used on this but a nice green) I used Krylon X-metals. I've seen them at Meijer, K-Mart, sometimes craft stores, hardly ever at Walmart/Depot/Lowes. They claim an anodized-like finish, and the caps look like anodized finish, but what they really are is a glittery, sparkling kind of finish. They need a silver primer, though, and take many many coats, as they're somewhat translucent. For example, I marked some lines with pencil (those nifty Fliskit mechanical pencils), and after 2 coats I could still see the pencil lines. On some of the pics posted, you can spot tube spirals. That's not because they weren't filled, it's because the filler material is darker that the body tube and the paint's not covering that up.

I will point out that the combination of my mediocre camera and urine-poor florescent lighting really don't show off the appearance very well. It looks a whole lot snazzier by daylight.

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chanstevens

Well-Known Member
Finished up Tuesday night, finally got around to unloading pics and posting the update...

I'd mentioned that despite all that construction and pre-painted parts all going together, there was still a bunch of work left. Well, let's start with the antenna. Starts off easy, with a little BT-2.5 (scalloped, can't have any standard looking tubing on this animal) tacked on top of a balsa fin (with yet another curved edge, very few straight cuts on this animal).

The front of the dish is a paper shroud, not too bad to make but not much "height" to work with. The backside of the dish is a scrap piece cut out of the ping pong ball hollowed out at the very beginning of the project. I hit the paper shroud with super thin CA, then gobbed on some filler to do what I could with the seam. The fun was in finishing--those are all sprayed on paints (and I love the metallic red up front). Try masking around the edge on this puppy--that dish is barely 1/2" tip to backside. What I wound up doing was slipping TC-50 coupler stock over the silver tube and butted it up against the back of the dish, then masked around that formed cylinder.

chanstevens

Well-Known Member
Next round of details were the guns. The four side/wing fins each have a length of 1/8" dowel attached. I went ahead and bonded/painted those with the main wings, then went back and hand painted them each with aluminum (not silver) Testors paint. That's one of only two aspects of this whole thing that wasn't rattle can or air brush sprayed. The other is coming up next post.

On the very ends of the little wing extension fins are guns made from toothpicks stuck inside a standard 1" length of launch lug, though the toothpicks need a paper or tape wrap to center in the lugs. Sprayed silver and red offline, tacked on with a really tiny trace of epoxy.

chanstevens

Well-Known Member
Last round of detail do-dads was for me, the sexiest aspect of this whole project. That ping pong ball, left hanging out there all by itself, would make this look too much like a Shrox kit (not that that's a bad thing). Soooo, Jim's got 8 laser-cut radial fins that start out on the BT-50 body tube, curve around the ping pong ball, swoop down and tack to the BT-20 body tube on a tangent, then curve back up to hold the edge of a BT-60 rear ring fin. I know Jim's older and has lost more brain cells than me, and I can't handle the math figuring out the curves, so how he got this to fit so well is amazing to me. There is just enough slop/gap between the ping pong ball and the fins to bug the anal-rententive geek in me, but with the choice of tack them on nekkid, fill, then paint over perfect seamless fit, versus paint contrasting colors offline and live with slightly imperfect gaps, I'll take the colors and minute gaps.

Did I mention there's a whole lot going on at the aft end of this thing? Cripes, look at all that stuff built up around a BT-20!

chanstevens

Well-Known Member
Aft end view of those radial fins, gently fingering to the BT-60 ring fin. Yeah, I was sloppy and didn't get them spaced with perfectly even spacing between each fin. If I'd used the marking guide, it would probably have looked better but I was afraid to put much tension on them figuring I'd dislodge them.

Now to think through how I'm going to get a motor in and out of there. Maybe Jim has a companion tool he's going to be releasing at NARCON .

chanstevens

Well-Known Member
Chan,

Very, very nice.

Would you mind giving us a list of the paints you're using. Those metallics look great. Really nice idea to use the decal stock, too.

Steve
Decal stock idea shamelessly stolen from evil genius Bob Cox, who used reflective tape to a stunning effect in his Q-Modeling Andromeda. With the trick of the camera flash, it really looked like he had some sort of powered LED system inside the side pods.

chanstevens

Well-Known Member
Two poopy views under poor light, hacked down to attachment size limits, but they give you a taste for how wonderful this kit can be to build.

General impressions--it is a fair amount of work, certainly more than the typical kit, though I would not say it takes exceptional skill, and the instructions are excellent. It's probably the most work you'll ever run into on a $35 kit (exception--Flis's peanut scale Saturn 1b). There are very few kits I've had to give as much thought and up front planning to, and I'm now over 500 in the built fleet. This is clearly not something you would want to build first, then decide how you want to paint/finish it. Even if building with pre-painted subassemblies, deciding how far to take any given subassembly before painting is a mental challenge. The fit and design are superb. The templates, instructions, etc. are impeccable. The decals, great designs, are the weakest aspect of the kit, and I'd almost prefer to have thrown most of them out rather than use them. They really needed to be printed over a base layer of white. As is, they're much too translucent, and especially weak against even the light blue and purple metallics. They're invisible against the black. The decals could really add a nice finishing touch, but given that they mostly blend into the dark backgrounds, I'd have to rate them a C- on what is otherwise an A+ kit. Those little black diamonds against the red of the ping pong ball look great. Those little alien symbols against the purple wing pods look like [fecal matter]. For those of you that bought one of these and either looked at the header card or the directions and panicked, look through this thread, realize start to finish was about 3 days part-time and 2 evenings, and toss aside the fear. This is a very buildable model. For those of you not sure you would want one, or thinking it's too steep, look around your fleet. Is there anything else in there even as remotely fascinating as this, for anywhere near$35?

Heck, this one scared me off at first, but once I hit the last decal with Micro Sol, I started to recognize this is one of those designs that I'll probably be looking back at 20 years from now and thinking is one of the classics.

If I don't manage to trash it in flight--first flight might be this weekend, though weather doesn't look good right now.

Gus

Well-Known Member
Chan,

Thanks a ton for this great thread. Absolutely gorgeous build of a truly fantastic kit.

I, too, really like the Rustoleum metallics and I wish they did actual colors. I've found the same thing you did with the Krylons, that they're very thin and tend to try my patience. The other metallics I've used are Testors but they tend to have the opposite problem and go on way too thick, stay wet too long, and tend to run (for me at least). But they do have great colors.

Anyway, thanks again for putting the work into such a great build thread.

Steve

rokitflite

Well-Known Member
Chan,

Thanks a ton for this great thread. Absolutely gorgeous build of a truly fantastic kit.

I, too, really like the Rustoleum metallics and I wish they did actual colors. I've found the same thing you did with the Krylons, that they're very thin and tend to try my patience. The other metallics I've used are Testors but they tend to have the opposite problem and go on way too thick, stay wet too long, and tend to run (for me at least). But they do have great colors.

Anyway, thanks again for putting the work into such a great build thread.

Steve
Try the new Testors lacquer paints Steve!

jflis

Well-Known Member
By the way, Jim--I know the aft end on this gets a bit crowded, but when I anchored the two main fins on, one of them wound up sitting right on top of the motor hook. Naturally, it was the second one, so trying to reposition it would have my fins not quite at 180 degree orientation. I might be off a little bit on my lines, but I suspect there's just not enough room for a main fin and motor hook in between two of those curved fins. If I were doing it over, I'd probably think about using a wire instead of standard motor hook, or maybe leave out the hook entirely and try tape retention, though getting tape in there around a motor could be a pain, too.
Chan, I looked over the instructions as I couldn't really understand the problem, till I looked closely... I never mention it, but when doing the fin marking guide on the BT-50 I need to put marks for the engine hook and have you align *those* instead of aligning the coolant fins lines.

This would force the engine hook to the correct place which is the very bottom of the rocket, away from any other fins...

Next pass

As for the decals, yea that's a concern... I am looking into silk screening those with a white backing.

Great build and a beautiful bird! very kewl

dragon_rider10

Well-Known Member
I must admit to feeling intimidated by the more intricate Fliskits. One day I will be man enough to tackle such a project. It can be done, and Chan ,thank you for showing me that it is indeed possible!

chanstevens

Well-Known Member
Chan, I looked over the instructions as I couldn't really understand the problem, till I looked closely... I never mention it, but when doing the fin marking guide on the BT-50 I need to put marks for the engine hook and have you align *those* instead of aligning the coolant fins lines.

This would force the engine hook to the correct place which is the very bottom of the rocket, away from any other fins...

Next pass

As for the decals, yea that's a concern... I am looking into silk screening those with a white backing.

Great build and a beautiful bird! very kewl
There will always be some slop in trying to align lines on tubes of different OD's. Best technique is to draw a line on the 20/50 ring, align that with a line on the BT-20, then align the corresponding BT-50 line to it.

The problem as I see it with the current kit/plan is that there are 8 different BT-50 coolant fin lines I could choose to align any given BT-20 line to. Depending on which one I choose, my hook will line up smack in the middle of something, because you've also got all those lines for lugs, fins, stabilizers, etc. I made a bad choice and my hook happened to land between two coolant fins that get a main fin between them. Had I rotated one more "click" with the next coolant fin line instead, I'd have a hook lined up behind a lug, or stabilizer, or something much better.

You need to make one of those BT-20 coolant lines a major/bold/alignment line, and one from the BT-50 the same. Allowing the modeler to just randomly line two lines up will result in a 25% chance of blowing it like I did.

I've always been out on the statistical fringe...

chanstevens

Well-Known Member
Launch photo courtesy of Launch Crue's Mike Borman. Finished model weighed in at 2.8 ounces, so I figured it would be fairly slow to climb, but it zipped up there pretty quickly. Might have rolled 1.5-2 times on the way up, but otherwise flawless.

The neatest thing, though was the voice-activated dual deployment technique I used for the chute. Very cutting edge. It was a bit breezy and temps in the low teens, so when the chute popped out but didn't unfurl, things got a little tense. I joked that it was dual deploy for a shorter walk. At about 75 feet, I called out that the chute could open any time now, at which point it did, right on cue. It opened up just in time to ensure a soft landing in the snow. Perfect flight, perfect landing, short walk. Rocketry doesn't get too much better than that.

jflis

Well-Known Member
I love it!

Man, she sure do look good in the air and painted

Bet *that* rocket wow'ed a few people

chanstevens

Well-Known Member
I love it!

Man, she sure do look good in the air and painted

Bet *that* rocket wow'ed a few people
There might have been 3-4 people actually outside when I flew, and it did wow that crowd. There were another half dozen staying warm in the heated shed prepping stuff. This beauty really deserves to fly for a bigger crowd, but I fly for my enjoyment, which this amply provided.