Radio controlled airplane

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montagdude
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Re: Radio controlled airplane

Postby montagdude » Thu Oct 10, 2019 6:04 pm

bill wrote:
Thu Oct 10, 2019 3:43 pm
Zolko wrote:
Thu Oct 10, 2019 2:01 pm
why did you put dihedral
For level flight stability; it looks like a camera-ship!

Does the wing come off for repair? Is it elevator/aileron? Is it electric; then where does battery fit?
No, the wing will be glued in place. It is rudder/elevator/aileron/throttle. The battery and the rest of the electronics that are not modeled will just be mounted to the outside of the fuselage.
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Zolko
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Re: Radio controlled airplane

Postby Zolko » Fri Oct 11, 2019 8:07 am

montagdude wrote:
Thu Oct 10, 2019 6:01 pm
As for the sweep, originally I had a straight wing, but after making some CG estimates, I realized it would probably be too far back.
montagdude wrote:
Thu Oct 10, 2019 6:04 pm
The battery and the rest of the electronics that are not modeled will just be mounted to the outside of the fuselage.
If the CG is too far aft, can't you correct it by moving the battery ? A swept wing with dihedral is going to be a PITA to make. A dihedral with straight struts is quite easy and light, a plane and swept wing is also easy, but the combination is difficult.
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montagdude
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Re: Radio controlled airplane

Postby montagdude » Fri Oct 11, 2019 1:17 pm

Zolko wrote:
Fri Oct 11, 2019 8:07 am
If the CG is too far aft, can't you correct it by moving the battery ?
The battery is quite small, and it was already as far forward as it could go. I didn't want to extend the nose.
Zolko wrote:
Fri Oct 11, 2019 8:07 am
A swept wing with dihedral is going to be a PITA to make. A dihedral with straight struts is quite easy and light, a plane and swept wing is also easy, but the combination is difficult.
I don't see why it should be so difficult. It's not like this is some revolutionary thing that has never been done before. All the ribs, spars, and strips are at right angles to each other with the exception of the root ribs. It will just be a matter of making sure those get mated together at the correct angle, and I have designed a jig to help with that (in purple).
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Zolko
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Re: Radio controlled airplane

Postby Zolko » Fri Oct 11, 2019 1:43 pm

montagdude wrote:
Fri Oct 11, 2019 1:17 pm
I don't see why it should be so difficult.
It's not the assembly part the problem, as that is easily solved (you don't even need a jig), it's the mechanical resistance. But you seem quite confident, I don't want to discourage you.
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montagdude
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Re: Radio controlled airplane

Postby montagdude » Fri Oct 11, 2019 1:56 pm

Zolko wrote:
Fri Oct 11, 2019 1:43 pm
montagdude wrote:
Fri Oct 11, 2019 1:17 pm
I don't see why it should be so difficult.
It's not the assembly part the problem, as that is easily solved (you don't even need a jig), it's the mechanical resistance. But you seem quite confident, I don't want to discourage you.
No problem, I don't mind constructive criticism. I even added a couple triangle braces (highlighted) at the root to help make sure I achieve the correct angle between the ribs and the main spar after considering your comments. But I don't understand what you mean about mechanical resistance. Mechanical resistance of what? Do you mean fitting the wing into the fuselage once they are assembled?
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Zolko
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Re: Radio controlled airplane

Postby Zolko » Fri Oct 11, 2019 2:25 pm

montagdude wrote:
Fri Oct 11, 2019 1:56 pm
Mechanical resistance of what?
the spar. Think "looping"
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montagdude
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Re: Radio controlled airplane

Postby montagdude » Fri Oct 11, 2019 2:47 pm

Zolko wrote:
Fri Oct 11, 2019 2:25 pm
montagdude wrote:
Fri Oct 11, 2019 1:56 pm
Mechanical resistance of what?
the spar. Think "looping"
I must admit that term means nothing to me, and a search didn't turn up much. I'm not really a structures person, but planes like this are so light and slow that there is really no danger of structural failure, barring a crash. I expect this one to cruise around 20 mph and weigh about 1/2 lb.

Thanks again for your comments.
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Zolko
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Re: Radio controlled airplane

Postby Zolko » Sat Oct 12, 2019 6:05 pm

montagdude wrote:
Fri Oct 11, 2019 2:47 pm
I must admit that term means nothing to me, and a search didn't turn up much.
If it's "spar" the term that you miss then I meant the wing spar.
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Re: Radio controlled airplane

Postby montagdude » Sun Oct 13, 2019 12:42 am

Nope, it's the "looping" term.
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bill
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Re: Radio controlled airplane

Postby bill » Sun Oct 13, 2019 11:23 am

montagdude wrote:
Fri Oct 11, 2019 2:47 pm
Zolko wrote:
Fri Oct 11, 2019 2:25 pm
montagdude wrote:
Fri Oct 11, 2019 1:56 pm
Mechanical resistance of what?
the spar. Think "looping"
I must admit that term means nothing to me, and a search didn't turn up much. I'm not really a structures person, but planes like this are so light and slow that there is really no danger of structural failure, barring a crash. I expect this one to cruise around 20 mph and weigh about 1/2 lb.

Thanks again for your comments.
This looping is probably referring to a "Loop Manuver", which can preceed the main wings "foldling-up" like a book slamming shut.
typically because of lack of sufficient wing-root-spar reinforcement.

Does the plane have a gyro for level flight? For camera ship, this makes it much easier especially since you have included rudder control surface.

Might choose to fly as-is and stay away from exponential servo/control rates; stick with proportional rates.
Just a suggestion!