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Old Dec 11, 2004, 07:17 PM
zed
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Singapore
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My own design...comments?

Hi,

Built a plane over 2 nights, utilizing one of the foam wings from Dean (steelhead). Didn't do any calculations or design, just cut the body shape using imagination. Comments?
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Old Dec 11, 2004, 07:22 PM
Brad
Joined Nov 2004
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Have you flown it?
It looks neat for a build yourself
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Old Dec 11, 2004, 07:33 PM
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Kalamazoo, MI USA
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Nice!
TLAR.
It looks kind of Magpie-ish.
Brian
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Old Dec 11, 2004, 07:53 PM
The Evil Twin
Garden City, GA
Joined Feb 2004
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Nice job! Lets get a flight report.
Matthew
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Old Dec 11, 2004, 08:37 PM
zed
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Singapore
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Magpie-ish? Hmm....doesn't seem similar to me. But I did use Doug's AXI motor mount to mount my speed 400 motor. Haha...this plane is basically a collection of all the unused things in my box - speed 400 motor, 7cell kan 1050's, hs55's..

Anyway, just came back from a test flight. The plane is kind of heavy, cos the fuse is made up of solid balsa sheets. (I'm not good enough to do the the complex frames, maybe my next build). CG must be off, cos the plane was twitchy. Turns weren't as smooth as i would like. Landing approach is soooo fast. Quite a slippery airfoil, it just keeps on going. Oh by the way just in case its hard to see in the photo, the wingspan is only 32inch.

Anyone knows how to fine tune a plane? It flies but not well. I'm a little clueless as to how to go about improving it.

I'm pretty happy how I managed to get something I designed to fly...haha.
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Old Dec 11, 2004, 08:42 PM
zed
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maybe i should give some credit to Doug, the "basic" idea of building a square fuse and securing the wing with rubberbands came from the smoothE. But of course it flies no way similar to the smoothe. Cos the wingspan, power setup and the total weight would give it a totally different flight characterisitic.

Zed
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Old Dec 11, 2004, 09:20 PM
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If that wing has no dihedral (I can't really tell) then you will not turn smoothly without ailerons. Dihedral would also help the stability.

Brian
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Old Dec 11, 2004, 09:47 PM
zed
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no dihedral at all
Hm....so does that mean I HAVE to have dihedral to use rudder-only?

Zed
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Old Dec 11, 2004, 09:52 PM
zed
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i have another one of those wing cores, maybe i will put in some dihedral. Whats the best way to do it? cut in half then cut an angle and glue back? how would you put the spar on the "v" shape?

Wow i'm learning so much with building...i'm loving it!

Zed
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Old Dec 11, 2004, 10:35 PM
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Jacksonville, FL
Joined Aug 2002
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Quote:
Originally Posted by zed
no dihedral at all
Hm....so does that mean I HAVE to have dihedral to use rudder-only?

Zed
Only if you want to be able to turn decently instead of just yawing.

Rick
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Old Dec 11, 2004, 10:36 PM
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Quote:
Originally Posted by zed
no dihedral at all
Hm....so does that mean I HAVE to have dihedral to use rudder-only?

Zed
With a straight wing, the plane is "skidding" sideways ahead to some degree when the rudder is used.
The dihedral will cause some banking through the turn helping the plane to change direction, not just orientation.

To give your other wing dihedral, cut it in half and make a support to put under the wingtip (2 or 3 inches high). Support the wing half (I tape it in place with masking tape) so the cut end is flush with the edge of your workbench and sand or cut it so it is at 90 degrees in relation to the bench top. Do the same with the other half and glue them together. You will need some reinforcement like strapping tape to strengthen the joint.

You will find it much easier to fly, and with 2 wings, you could add ailerons to the straight one.

Enjoy,

Brian
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Old Dec 12, 2004, 01:18 AM
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USA, IN, Carmel
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with no dihedral, you'll be lucky to stay in the air at all. the plane will slip from side to side constantly... and you'll need ailerons to recover the plane when it falls off to the side... I've been there
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Old Dec 12, 2004, 02:04 AM
Rat
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Rats nest Grafton ND
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Tape the rudder straight then move the rudder servo to the middle,top of the wing. Cut some ailerons and tape them to the wing. Now find the servo horn that extends to both sides of the servo. Install that and run a control rod from each side to the ailerons. So when the servo rotates one way it will pull one aileron up while pushing the other aileron down. Now you can fly it only using the elevator, ailerons and throttle. No need for the rudder.
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Old Dec 12, 2004, 10:34 AM
zed
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Singapore
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Thanks for all the advice guys!

wattsup_kz: I will follow your instructions to do the dihedral, but how do I put a straight spar into a dihedral wing?

rat: Putting the ailerons seem like a good idea. Maybe i'll take out the rudder.

Zed
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Old Dec 12, 2004, 10:47 AM
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Cut the spar in half. The strapping tape takes the place of the spar in the middle. For details you can go to www.jkaerotech.com and look up the T-52 build instructions where they show the wing construction. That makes a good strong dihedral joint.
The Magpie build threads show a similar type of joint.

If you go with ailerons, you can keep the wing straight.

Brian
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