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My new cluster

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JeffS

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Here's a picture of my 3x24 cluster, just finished last week. It uses a 34" bt70 tube, Apogee nosecone and a FlisKits 3x24 motor mount. Giant Leap conformal launch lugs, 24" Apogee nylon chute, Loc style shock cord mount and 8 feet of 3/8 elastic shock cord. 3/16 Balsa fins.
After I got the first coat of primer on I thought that the body tube seemed kind of "flexy" so I cut it in half and put in a 4" coupler.
I'm thinking about doing the same rocket again with plywood through the wall fins and a 29mm mount.
 

JeffS

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Here's a picture of the first flight (E9's). It went pretty straight, pretty high. I think the 24" chute was too much because it drifted quite a ways. Two of the motor tubes were toasted a little on the ends and the paint at the bottom of the body tube blistered a little, otherwise it was fine. The motors were hanging out of the tubes about a quarter inch, maybe should have been a half inch?
 

Rocketman35

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Nice rocket! clean lines are classic!
Can we get a detailed parts list?
 

DynaSoar

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Originally posted by JeffS
Here's a picture of the first flight (E9's). It went pretty straight, pretty high. I think the 24" chute was too much because it drifted quite a ways. Two of the motor tubes were toasted a little on the ends and the paint at the bottom of the body tube blistered a little, otherwise it was fine. The motors were hanging out of the tubes about a quarter inch, maybe should have been a half inch?
Nice lines. Looks like a Vulcanite. 3 E9s is one of my favorite clusters to fly.

The burning is probably from base drag. Another 1/4" probably won't make much difference. Did you fill in between the motor tubes? If they're open they'll pull a heavy vacuum. A small deflector on the trailing edge of each side of each fin up near the root, angled to push some airflow under the base, might help fill in the vacuum.
 

JeffS

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Let's see...
Apogee nosecone PN 19470
Balsa Machine Bt 70 body tubes PN T70-34
FlisKits 3x34 motor mount PN EMK3-24-70
Acme conformal launch lugs 1/4 in. from Giant Leap
I also got a plywood 3x24 centering ring from Balsa Machine and epoxied it to the top of the motor mount to block ejection gases.
Motor retention was a screw epoxied into the center of the back of the motor mount with a washer and wing nut.

I think that takes care of the big pieces.
 

JeffS

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Did you fill in between the motor tubes?
No, like I said above I sealed the top, but the back was left open. (sound of smacking forehead). I'll see if I can't fix it before the next flight. Thanks!
 

eugenefl

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Very nice rocket indeed. Nice job. Sometimes the simplest of rockets look better than the complex ones. Either way, it looks like a rocket you enjoyed building and flying.
 

JeffS

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Thanks, I did indeed enjoy building it. Last winter I got away from rockets for awhile and looked at some RC airplanes and stuff, but I have to say, nothing stimulates my imagination more than building a rocket. My wife thinks it's some sort of wierd disease!
 

Micromeister

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Originally posted by JeffS
Thanks, I did indeed enjoy building it. Last winter I got away from rockets for awhile and looked at some RC airplanes and stuff, but I have to say, nothing stimulates my imagination more than building a rocket. My wife thinks it's some sort of wierd disease!
Great job Jeff!
Clustering now my second favorite part of flying...Yea my wife tells me I'm a sick puppy all the time;) mostly with the Odd-Roc's but with the clustering also. I'd still rather cluster BP then fly a single AP anything...just my bent but I love the extra fire and smoke.
Ever see a 4 D12 cluster at night? check it out
 

JeffS

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Ever see a 4 D12 cluster at night? check it out
Now that's cool. I have to admit, clustering is fun. I have been thinking about a good winter project and am leaning toward a 2 stage cluster, 5 motor booster to a single motor sustainer. The Fliskits 4x13+1x24 mount looks interesting, maybe with a bt60 size sustainer with either an 18 or 24mm mount. The center 24mm tube could be extended close to the sustainer and gap staging used. Oh well, I guess that's another thread.
 

jetra2

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I really really like the clean lines and paint job on this rocket, Jeff. Great job!

As for the 5 motors to a single motor, I say GO FOR IT! That'll be SCHWEET! One thing I like about the BT-70 (2.217" OD) is that it's one of the bigger tubes, and makes for an impressively sized model when it's built! Post a lot of design details when you do!

Jason
 

Micromeister

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Yes that could be another thread. only cluster/staged a couple models. bigest being a 3X upscael Laser-X with an active upper stage. I've only flown it staged once since I had to walk about 3 miles to find the sustainer which was flown on an A8-5 motor! 3 D12-3's to the A8 put the very light sustainer out of sight. I got lucky the 18" chute snapped a couple shrouds acting more like a streamer then a chute. now I lock the sustainer to the booster and fly it as a single stage clustered upscale...If you have a HUGE flying field and make the upper stage pertty good sized you may get lucky and get it back:)
I didn't gap stage this model, it has a mercury switch/9volt upperstage ignition system housed in the transition which is Rolled 3/64 aircraft plywood.
Sounds like a neat winter project. Start a new thead when you get going with it;)
 
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