Carbon X, 29mm min dia rocket

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Tominator 2

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Hello everyone,
This is a continuation of my other thread on carbon fiber finishing. I decided to build a Carbon Fiber minimum diameter rocket using carbon fiber sleeves from soller composites. I call it Carbon X (I think it sounds kind of mysterious:eek:). It is 27 inches long (not including the nosecone) and a little more than inch and a eigth in diameter (29mm). Should be really cool when its done.

I tacked on the fins using 5 minute epoxy last weekend. Yesterday I did fin fillets using collodial silica and epoxy. They look pretty good. The fins are 1/16 plywood. Today I hope I get a chance to do some tip to tip glassing. My plan is to use 2 oz part of the way and the rest tip to tip 3/4 oz glass. What do you guys think about that? The biggest motor that I plan on using on it is an H motor. Im kind of nervous for the tip to tip part because there is a lot at stake.
Here are some pics that I took last weekend. Havent taken any pics with the fillets but ill try and get some soon. Hope you guys enjoy them.:cool:

View attachment Carbon X one.JPG

View attachment Carbon X three.JPG

View attachment Carbon X four.JPG

View attachment Carbon X two.JPG
 
Hey it looks good, and i know what you mean about the nerves with the tip2tip...Im trying to find some time to to tip2tip on my 38min CF rocket :/
 
Looks like a good start so far.

Not that I'd want to get in the way of getting this done today, but if you used some unidirectional carbon from www.cstsales.com and you'd need a lot less thickness and mass for the same stiffness than you would for FG cloth. The uni fibers would make the fins amazingly stiff and strong in the direction that the fins usually bend, and your .0625 plywood should be plenty to take care of the stiffness and strength in the other directions.
 
Thanks guys for the comments.
Tennisce, Yeah I really hope I don't screw up. :)
Adrian, I was thinking about unidirectional fibers for this application. What about laying them on both axis? How long would it take for it to ship?
 
Tominator,

The shipping time was pretty normal, if I remember correctly. 4-5 working days ground, with faster options available

With the fibers running from one tip to the other you'll get the best bending/fluttering resistance. If the fibers are parallel to the direction of flight, they would only really help keep the fins from bending in the other direction, the direction which is already constrained by the fact that one edge is stuck to the airframe. The plywood should already make it pretty ding resistant and would provide a good base to prevent the uni fibers from splitting, so if it were me I'd just save the weight and thickness and just put the fiber all in the tip-to-tip axis, with maybe a thin layer of FG for the surface finish that you would mostly sand off.
 
Hmm, interesting. I will have to look into that. What weight do you recommend?
 
I'm not completely sure because I bought it by feel at my local composite supply store. It's satin weave, very fine, and I think it's either 1.6 or 3.2 oz/sq yard.
 
It's pretty straightforward. All of the dry unidirectional cloth has some sort of net backing to keep the fibers together and flat. Some of the nets work better at that than others. I haven't seen pictures of your fillets yet, but they need to be decent size so that the bend radius of the fibers is reasonable, like maybe 1/4" radius.
 
Ok, well I will post pictures of the fillets over the weekend so you can see the size of the fillets.
 
Couple of questions.

1. Since you're going to such lengths, is there a reason you went with plywood fins instead of layered and bagged CF or perhaps a honeycomb type of composite and cover that in CF?

2. What are you using for recovery as well as how do you plan on finding this thing once you shove an H or even G for that matter up it's backside? You're not even going to be able to see it leave the pad it'll be so fast.

Is there a possibility it'll go supersonic?
 
I really like what you've got going...

If its 27 inches without the nosecone, there should be enough room to strap a loud beeper or radio locator to the shockcord and not have to worry about it.

As far as the fins, honeycomb composite fins from GLR are amazing and incredibly light. But it probably won't make too much of a difference with the 1/6th ply after 1-2 layers of composites are rolled over it.

I would assume that this rocket can go mach on a G motor, its been done with a LOC Aura which isn't even minimum diameter. According to Rocksim, I came pretty darn close to mach with my F-altitude rocket. You just really won't be able to truely know unless you have onboard electronics because Rocksim starts getting a little hairy in the transonic stage of flight when it comes to accuracy of velocity.

Good work!
 
Ian, thanks for addressing my newbie questions. I just launched my first G motor two weeks ago. I wasn't questioning the contstruction but more or less questioning the reasoning because I think it's cool. I have had some experience w/CF and honeycomb materials for air dams, spoilers, etc. on some different race cars I've observed in my fabricator's shop which is where the materials questions stemmed from.
 
1. Since you're going to such lengths, is there a reason you went with plywood fins instead of layered and bagged CF or perhaps a honeycomb type of composite and cover that in CF?

hounddwgrcing,
Yes, that was all I had laying around my garage. and I do not have vacum bag setup (yet).
I think I'm going to do what adrian suggested, the fiberglsas over unidirectional CF.



2. What are you using for recovery as well as how do you plan on finding this thing once you shove an H or even G for that matter up it's backside? You're not even going to be able to see it leave the pad it'll be so fast. [/QUOTE]


My plan is to use metallic streamer for recovery. I think with some luck and some help with a beeper that I can find it. I live in Socal so a dry lake bed is not too far away.


Is there a possibility it'll go supersonic?

Yes, I think it could go supersonic on a G80. But that motor will not be the first flight for obvious reasons. Im planning on something like an E15W for the first flight.
 
Pyrovette,
That is really cool. How fast is it supposed to go? ;)

chicagonative17,
Thanks for the comments. Im going to go for the beeper. and an altimeter probably. Where would I find a beeper?
 
Pyrovette,
That is really cool. How fast is it supposed to go? ;)

chicagonative17,
Thanks for the comments. Im going to go for the beeper. and an altimeter probably. Where would I find a beeper?

No idea how fast .It is a Kosdon J604 slow propellant.The fast comes in around a J1000. Just a 5' fiberglass tube and fins. Now I gotta make a tower for it.
 
You can find a good beeper at transolve.com and they have 3 available beepers, all in different sizes. The two loudest (and largest) produce over 100 dB. The big one is only $30 and has over a 40 hour battery life. Check out the website, I'm sure you'll find something you like.
 
I would think that a less expensive, smaller, and lighter weight solution to "tracking" would NOT be a (loud) beeper when compared to this;

< https://jbgizmo.com/page32.htm >
https://jbgizmo.com/page32.htm

I have flown this transmitter and with the correct GSE you can EASILY get bearings even on fast moving rockets you cannot see (or hear). After it lands you are able to walk right up to the landed rocket. It really is a cinch. You can even walk past it, know you have done so, and then know in what direction to turn and get a new bearing in a few moments.

And should you not be able to spend the time right then to find the rocket, the battery life is measured in weeks.
 
Hmm, Interesting. I will have to look into those. I haven't got any pictures of the fillets yet because last night I was busy packing for my trip. I will get back this weekend so ill post pics of the fillets then.
 
Haven't posted on this thread in a while...
I have been busy lately and took a while to decide on the CF i was going to get. But i finally bought some 2 oz carbon fiber from cst sales as well as some peel ply. My plan is to use the tip to tip jig as seen on john cokers site:

https://www.jcrocket.com/tttjig.shtml

And on John rockdales site with his shock value: :cool:
https://www.jrockdale.com/shock.htm
I think they did an excellent job on there rockets and I hope i can replicate there results! :D
Will start the fincan next weekend. Im excited and nervous!:)
 
Thanks, progress is slow but getting there...
What is your experience on the locator? Whats the range of it?
-Tom
 
Looks good Tennisace! How have you trimmed the excess carbon yet? If so, did it bond well to the leading edges?
 
Thanks, and yes it did except for one small spot less than 1/8" that didn't get wetted out all the way. But a little CA and sanding it it will be perfect :)
 
thats awesome! what about the breather material? I didnt order any. Could i go without it?
 
The breather soaks up excess epoxy so that you dong get any high spots with epoxy. With out a breather the epoxy will squeeze out the sides or just make a hight spot that will need to be sanded. I also think it helps reduce wrinkles, but it depends on your lay up process. If you using just peel-ply and a back with sand, just make sure the part in contact with the peel-ply is flat and as few wrinkles as possible. Then after the fabric is fully wetted out, try to squeeze as much epoxy out of the fabric before you but the peel-ply on.

Anyone else have any comments with not using a breather???
 
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