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ActingLikeAKid

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I picked up a few Flutter-By kits when they were less than a cheeseburger. And while the cost is great and means that I don't cry if I lose them....

....I'm thinking of letting my kids build them. And if *THEY* lose them, there will be tears. So I was thinking - how hard would it be to connect the two halves with a couple of feet of Kevlar cord (the "thread" kind, not 1/8" tubular or anything) and stick a streamer on it? Replace or augment the clay in the nose with some epoxy to hold in one end of the cord... Am I missing anything? Good idea? Bad idea?
 

watermelonman

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I tried similar, by simply tethering the two sections. It seemed to work great when I threw it up into the air.

Sadly on first powered flight the charge blew out hard enough to break the nose cone attachment point. I think getting enough kevlar line in place to dissipate the ejection force will be difficult.
 

GlenP

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I have seen one of those in flight, the ejection is pretty powerful. I wonder if you could tame it a little with a couple of small vent holes strategically placed, not too big, but not too small, may take some experimenting.
 

adrian

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Make a 13mm-18mm adaptor. The quick'n'dirty way is to just knock the clay nozzle out of an expended 18mm motor, then a 13mm motor will fit neatly into the empty casing. A 13mm ejection charge should be less powerful than an 18mm charge, plus you get four motors for the same price as three 18mm. You're limited to A class, but that may not be a bad thing if you're worried about kids getting upset when the rocket gets lost - and if you want to put a C in it anyway, you can always take the adaptor out.

Does that kit have a plastic or balsa nose cone? If it's plastic, and has a hole in the base, you can stuff a kevlar cord (or most of it, if it's really long) into the cone.

Depending on what sort of surface is at your flying site, you may not need a streamer. The Flutter-By looks small and light enough that simply blowing it in half and letting it tumble would be enough. But not if you're dropping it onto concrete or packed dry earth, unless you like gluing fins back on.
 

hcmbanjo

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I have seen one of those in flight, the ejection is pretty powerful. I wonder if you could tame it a little with a couple of small vent holes strategically placed, not too big, but not too small, may take some experimenting.
I recently launched mine with an A8-3. At ejection the nose section was knocked 200' away from the low end half which landed closer to the launcher.
The upper half landed in high grass. I stepped on it and cracked the root edge glue!
 

Mushtang

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I have seen one of those in flight, the ejection is pretty powerful. I wonder if you could tame it a little with a couple of small vent holes strategically placed, not too big, but not too small, may take some experimenting.
I recently launched mine with an A8-3. At ejection the nose section was knocked 200' away from the low end half which landed closer to the launcher.
The upper half landed in high grass. I stepped on it and cracked the root edge glue!
Experiment successful. Embiggen the holes slightly and fire again.

:D
 

Mushtang

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How big and how many worked for you?
It was sort of a joke. HCMBanjo had said he stepped on his, so obviously it couldn't be fired again. At least not without some work.

I've never built or flown one of these.
 

swatkat

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The halves seal pretty good. Ours pop like bottle rockets at apogee. I just bought 5 kits and expect we will have a few lost halves over time. The kids love them tho. I wouldn't launch on anything more than a B6-4, they go high.
 

Kirk G

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Isn't the Flutter-By a rather primative rocket...?
That is, isn't it an A8-3 motor and Skill Level ONE?

As I understand that, it's basically RTF, and takes almost NO skill at all to assemble and then fly?

Is it designed for bored kids who can't wait to build their own?

Comments?
 

Steve Shannon

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Isn't the Flutter-By a rather primative rocket...?
That is, isn't it an A8-3 motor and Skill Level ONE?

As I understand that, it's basically RTF, and takes almost NO skill at all to assemble and then fly?

Is it designed for bored kids who can't wait to build their own?

Comments?
Just one, any rocket's better than being shamed.


[emoji1010] Steve Shannon [emoji1010]
 

dhbarr

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Primitive is a MD tubefin made from copy paper using friction fit and flutter recovery. And that's awesome!
 

TopRamen

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Isn't the Flutter-By a rather primative rocket...?
That is, isn't it an A8-3 motor and Skill Level ONE?

As I understand that, it's basically RTF, and takes almost NO skill at all to assemble and then fly?

Is it designed for bored kids who can't wait to build their own?

Comments?
I have a Flutter-By Kit that was given to me, and since you look at it like that, I think I may build it in my typical over-complicated fashion.

Jeez!! Just when I think I don't have enough builds going. I'm not a "Bored Kid", and prefer to buiold my own, but to be honest, the kit is intimidating to me, so I have not even read the instructions yet.

I'll go grab it and fuss about with it for a bit.
 

TopRamen

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Holy Crap! Pre-cut fins!

Have not seen or used those for awhile!

Flutter-By 2016-06-19 002.jpg

There are only 12 parts, and one of them is clay for nose weight, so this appears to be my kind of kit.
Bye-Bye Clay! Say hello to leads shot and epoxy.
I'll use the clay for reference as to weight, but really I should not depend on that, as I don't see a quality control stamp on the tiny plastic pacakage it is in, and while it feels great and malleable, I have not controlled it since it's point of manufacture, so I will be the judge of how much nose weight it will need, and it will be greater anyway, since I have composite 18mm motors and carbon fiber.
I wonder what Openrocket will say about this one when it comes to warnings????
I can weigh stuff to the tenth of a gram now, so I should be able to make all the components, weigh them individually, then add the weight of any adhesive needed to the override portion of the OR Design Sequence.
Stay tuned!
 

ActingLikeAKid

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Holy Crap! Pre-cut fins!

Have not seen or used those for awhile!

View attachment 294536

There are only 12 parts, and one of them is clay for nose weight, so this appears to be my kind of kit.
Bye-Bye Clay! Say hello to leads shot and epoxy.
I'll use the clay for reference as to weight, but really I should not depend on that, as I don't see a quality control stamp on the tiny plastic pacakage it is in, and while it feels great and malleable, I have not controlled it since it's point of manufacture, so I will be the judge of how much nose weight it will need, and it will be greater anyway, since I have composite 18mm motors and carbon fiber.
I wonder what Openrocket will say about this one when it comes to warnings????
I can weigh stuff to the tenth of a gram now, so I should be able to make all the components, weigh them individually, then add the weight of any adhesive needed to the override portion of the OR Design Sequence.
Stay tuned!
This should be exciting! I still have one kit in the box, I scavenged the coupler/adapter from one of them to do a repair to one of the boys' rockets (which - pat on the back - went pretty seamlessly). I think shot would be a better idea. The one I did have was kind of corkscrewy; I'm blaming uneven application of the clay.
 

TopRamen

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This should be exciting! I still have one kit in the box, I scavenged the coupler/adapter from one of them to do a repair to one of the boys' rockets (which - pat on the back - went pretty seamlessly). I think shot would be a better idea. The one I did have was kind of corkscrewy; I'm blaming uneven application of the clay.
I'm excited about it too, but my hands spent all day sweating in nitrile gloves, and they dried out tonight, so now my stupid skin is all tight and tearing.
Thankfully, I heal quick, so I'll get right on this crazy ass Flutter-By tomorrow in conjunction with my other builds.
This is a scary Kit!!!
I wonder who designed it, even though I know it was originally a Centuri Rocket.
Yes I am going to bastardize it, but that's just the way it is.
Guess I'll have to research it too, since I can't rightly talk about what I'm going to do if I don't know what I'm playing with.
I do hope this is not a dead end when it comes to research.
 

kcobbva

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This is a fun little rocket! My daughter built her's over this past winter. Still haven't launched it due to stupid regs where we live. July 16! Finally gonna launch it and 4 others that have been sitting here! Have fun with yours!
 

TopRamen

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I managed to pop all the pre-cut parts out after some wigglin' the balsa sheet, and do some research on rocketreviews, so it looks like it will atleast be done pretty quick.

I normally cut the pre-cut stuff but this is meant to be a doable quick and dirty build to answer the question.

That answer always ends up being "Fun".
 

TopRamen

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The Body Tube is nearly non-existant, but we'll lose the glassine anyway and apply it to the Mandrel for this size tube.
I'm going to have some fun, but only if there are not a billion insects on my porch, as the wrap of this tube is incredibly poisonous/noxious.

Flutter-Bye-Bye 2016-06-20 001.jpg
 

TopRamen

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The BT took all of three minutes.:)

Because I Can 2016-06-20 001.jpg

And since I know you want to see the seam:

Because I Can 2016-06-20 002.JPG

I'm getting better is what matters.
 
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GlenP

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One pair of fins is glued above the notch, the other pair is glued below the notch. This leaves a large part of the fin with grain direction not optimal, and prone to breaking along a grain line above or below the glue seam. This almost begs to be a two part fin where you change grain direction at the notch. keep the glued portion grain direction, but change the grain direction of the unsupported portion to be parallel to the tube. Might need another short strip for the leading edge to round it off as well.
 

TopRamen

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That tube I made at 1:45AM looked like crap in the light of day, so I made another which turned out great, then made a mandrel for the tinier tube and peeled it's glassine layer for CF too.
The bonus of this build is that I have a 18mm mandrel now, and by making it of rolled paper, I learned a new way to make mandrels to the exact size I need.
I'll just use the fins that came with the kit for templates, as they are already too thick to start adding layers too, and there is no reason to not make them out of paper, fiberglass and carbon fiber. The finished fin will be thinner than the balsa fins, and so much stronger, yet still incredibly light, so I can't wait to compare the two down to the tenth of a gram!!! My fins are going to kick ass!
Since this bird requires no fillers or paint, it will hopefully weigh close to the original specs. That glassine I removed weight a few grams, as it is the heaviest part of any tube. after removing it from a few tubes to see what it weighs, I am ashamed I ever used to only rough it up to get good adhesion. It's like 30% of the weight or more of any given tube.
I did not have much time to dedicate to this today, as I'm still finishing building my carbon fiber Macklin Fin Jig.
Flutter Bye-Bye CF 2016-06-20 004.jpg
 
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TopRamen

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So is that an overlap or a gap that's filled with epoxy?
It would have been, but I got really good at making the seam line up, so there will be no epoxy needed.
Even the 18mm part came out with a nearly invisible seam, but there is a lip there if you measure it with the caliper.
It can be filled with rubbed on CA, which is not nearly as heavy as Epoxy, but I will maybe use some epoxy somewhere on this build.

Flutter Bye-Bye CF 2016-06-20 005.jpgFlutter Bye-Bye CF 2016-06-20 006.jpgFlutter Bye-Bye CF 2016-06-20 007.JPG

Shaping the motor hook to conform to the parts it gets sandwiched between means the circumference of that huge cardboard piece does not change, so it can still slide freely out of the 24mm tube.
Speaking of which, there is no reason not to skelotonize that component, as it sucks the CG toward the rear of the rocket.
Stupid unnecessarily massful component!!!
I don't want to distort anything, even though that is hard to do with machinable parts. The Green coupler piece has been hardened with CA and tuned properly.
I'll make a disc for it that hides the fact that it is cardboard, but only on the outside when the rocket is in it's one piece config, and the disc will match the circumference of the 24mm tube, so that the rocket looks like it is one piece when assembled properly.
It will also add rigidity, and since it will be less than a tenth of a Gram, why not incorporate it?
I absolutely love fitting these tiny parts that can be worked with custom sanding tools and files.
 
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TopRamen

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I think I have a solution to keep the two halves connected for descent.
 

GlenP

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The original post was more concerned with losing the parts. Streamers could be attached to both parts, they don't have to stay together, a colorful streamer might make the parts easier to find in tall grass.
 
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