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my new cheetah is here and assorted topics

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spacecowboy

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My new Astrobee Cheetah arrived.
If anybody has some "don'ts" I'm all ears.
So far I have destroyed Astrobee AD and given Executioner a lobotomy from it's core sample trip.

I sort of think this belongs in the reco section, but I think I'm on to something, which I seem to recall has been mentioned before.

Putting a centering ring closer to the NC, in both my MPR's, would have probably helped, at least some. For one, it would keep all the reco matter above CG, thus keeping the roc more stable. Might help reco chances too. For now, I'm going to be using wadding instead of barf. It seems to stay put better, and also really helps chute burn, even in LPR
 

Darian Rachal

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Space cowboy, I had a Cheetah until I lost it last weekend at a launch. I really liked it. I flew it a number of times at a small field on a D12-5 & I imagine it'll fly well on an E9-4 or 6.

It flew well on the Econojet F & Gs.
 

Initiator001

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I finally 'retired' my Cheetah after nearly fifty flights. It's still flyable.

I built mine per the instructions using medium CA adhesive.

My only comment is that the rocket lands on the tail end of the body tube, not the fins. If I build another Cheetah, I would strengthen the body tube, possibly by soaking with CA.
 

rbeckey

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When I have a rocket that has BT hanging below the fins, I slide a coupler in there as far as it will go and draw a line on it where the BT ends, then pull it out, cut it to length and glue it in.
 

jetra2

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I did a techniques similar to this on my Astrobee D. I had extended the fin slots so that I could build the fin can as one piece. Well, this of course left me with four pieces of weak bodytube. So, I took the provided coupler, inserted the fin can, pushed the coupler in against the lower CR, drew a line around the coupler, then cut through. In this post, you can see a picture of the area before the coupler.

Jason
 

jetra2

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Now here's a picture of it with the coupler installed but not cut.

Jason
 

jetra2

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And finally, here's a picture to show how much added strength the coupler adds to this area. It's now a double walled body tube! Now it's time to work on those fins....

Jason
 

n3tjm

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The Cheetah flies great with D12-3, D12-5, and E9-4 motors. I loved flying mine with a E9-4... Now it is hanging in a tree :(. Been there for over 2 years now. :(
 

spacecowboy

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I get the idea that anything bigger than E9 is a tree ornament, correct ? I also get the idea that Cheet' floats a ways on that big chute ?

I want just one MPR successful shot in the E30+, F20 ? range.

If I take Cheet' to AARG (Austin Area), I ought to be able to bring it back home if the wind is calm. I think E30 is 1800 ft, which is just outside the visible window, and I've got lots of volunteer spotters.

Of course, I put my 1/2 sized bash of StormCaster on a D12, and chased that joker for over a mile (it was windy).
 

loopy

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Put a smalller chute in it, or maybe a big, wide streamer...The thing is really light, and if it's built strong enough, it should do fine on a streamer, I'd think...
 

spacecowboy

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Cheet' is enormously easy to build. It helps that I dealt with AT and fin-lok before, on the AstrobeeD I destroyed.

About an hour, most of the biz end is done, including the 24mm adapter. I managed to goof up and glue the rear CR on, I don't think that's such a biggie, just going to have to take my time with the fins. UH, YOU NEED serious arm muscles to wrestle this thing together, even after following the directions "to sand". Very close tolerances with ATs
Unlike AstroD, I'm putting this one together before I paint parts, especially since I goofed on that rear CR.

I had a paint scheme dreamed up, and then I thought of something else, and then I was in paint-day-dream-land and never came back . . . .

Get'n Cheet' together pic.
 

loopy

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The easiest way I've found to put the fin lok rings on is to use my bench vise. Sand the outside edge of the tube, and the inside edge of the ring a little so you can just get the ring started on the tube, then position the ring on the top of the vise so that the ring hits the vise, but the tube can slide freely between the jaws of the vise. This allows you to use both hands to push down on the tube to get it properly positioned. Works pretty well, and keeps you from ripping your hands apart on the fin loks...

Loopy
 

n3tjm

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What I do for those BIG motors is tie the shroud lines together near the top, so the chute can not open all the way. I have launched my Arreaux and Cheetah with G80's using this config, and so far I have gotten them back :D
 

spacecowboy

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Here she is ready-to-fly.
I've never done leading edge paint on fins, or any kind of "transition" paint. I thought the diamond shapes were definitely cool
I should have stretched the height a bit taller, oh well.
 

loopy

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That's really cool! I like that paint scheme alot! When you launching, and what's it going up on? huh, huh, huh???
 

rbeckey

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Try an Applewhite 10 inch 29mm saucer with a G64, or a 7.25 inch 24mm with an E18. Perfect flights every time and falls within 50 feet (at the most) of the pad every time. My family loves these flights. In my opinion thet are just as thrilling as a midpower 3fnc rocket any day of the week. The construction is unique and you will find that it is cool to get to see the whole flight. They are also inexpensive compared to most midpower birds.

http://www.artapplewhite.com/fs.html
:cool:
 

raw9jr

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The Cheetah really goes nice and HIGH on a G, pick a calm day and big field and you'll be fine. Goes good on Fs too, but a G really sends it.
 

spacecowboy

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Loopy,
BABY STEPS.

all this was in previous posts.
My first MPR, Astrobee AD, G80. I had numerous reco problems, buried and basically destroyed it.
My second MPR, Estes Executioner, in high winds. E9, it cartwheeled across the deck about 10ft up. One more launch, E30, perfect flight, but reco problems, and it's 6" shorter now.

This Cheet', depending on weather, to see how far up the ladder I can climb. Probably in this order :
D12
E9
E30
F40
G? maybe.

I have to put this in here for the hoity-toity types.
Cheet' is flying first at a semi-private, invitation only, black tie optional event called TourDeDeuce in MO, around mid-March.
 

jetra2

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Originally posted by spacecowboy
Cheet' is flying first at a semi-private, invitation only, black tie optional event called TourDeDeuce in MO, around mid-March.
:D :D :D

Jason
 

loopy

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Originally posted by spacecowboy


This Cheet', depending on weather, to see how far up the ladder I can climb. Probably in this order :
D12
E9
E30
F40
G? maybe.
Cooollll...Given any thought to the E16? Might be a good match for that one.
 
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