swing wing help

Discussion in 'Aircraft & Aviation' started by freddyman, Oct 19, 2012.

  1. freddyman

    freddyman newbie

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    hello modelers. i have a question for you. i am scratch biulding a PANAVIA tornado in 1:72 scale.i have been testing multiple ways for a accurate swing wing disign but always ended up either weak or jams. can eny of you pinpoint me to a reliable souce. thank you
  2. Zathros

    Zathros Guest

    Make a partial gear connecting the wings. (not to scale obviously) :)

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  3. freddyman

    freddyman newbie

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    i have tried that disign. it jams like crazy fo me. perhaps i can try again.
  4. Zathros

    Zathros Guest

    It is really important to define the center of the radius. That is while it will jam. One way would be is to make 2 gear wheels, cut out the arcs you need, you will know that the gears mesh (choose the proper gear, not all gear teeth mesh with themselves), and make sure to put a pin in the centers. Try the gears side by side before you cut the arcs. when they turn smoothly, the piece of paper underneath, that has the two pin wholes, will be your location template, then you can cut the pieces out of the gears you need, and glue the wings to them. Personally, I would laminate the gears and maybe put some crazy glue on the gear surfaces so they are hard and work smoothly. :)
  5. trt

    trt Member

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    I would think trying to get gears to mesh correctly at 1:72 scale is going to be hard which ever way you try. You could just try a linking bar from the back on one wing to the front of the other. As one moves it would drag the other one with it. Or try as curved piece of card linking the wings through a small slot (the same width as the curved card). The wings would have to be very close together, so there is no slipage, but hopefully should move together. I've tried a crude drawing below.

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  6. Wojtee

    Wojtee Member

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  7. freddyman

    freddyman newbie

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    a slip rod will definatly work but the problem is that i also want to make this tornado flyable. and using this method ceated so much drag for my aardvark model that it will stall with wings open. thats the reason i trying anouther way to make swing wings.i trying out trt sctch though. looks simple and reliable
  8. Zathros

    Zathros Guest

    If ou want to make it flyable, you will have to make the center of gravity change with the model. If it is a powered model, electric or gas, different story, a glider though will not work properly with the wings swinging and the center of gravity remaining the same.

    If you give a a picture of the wings, I will draw the gears for you, attached to the wing ends, at the size you need. I will need a picture of the fuselage to determine where to put the centers of the pivots. Send me a P.M. if you wish to arrange this. :)
  9. freddyman

    freddyman newbie

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    actually just moving the wings is a change in center of gravity. a pull rod is not a very useful design for flight i admit but a gear design will make it lighter and decrease drag. not to mention that pulling the wings forward will send the gear back; making it slightly tail heavy, something a large wing area needs on a speedy airframe.a very kind preposition zarthros. i see if i can get that arranged

    freddy
  10. Zathros

    Zathros Guest

    You are moving the weight back, that could make the plane tail heavy, the center of lift is also changing which is of more consequence than the change of weight in the light weight of the wings. The change of lift will cause the plane to go into the ground, as it goes to the rear of the craft, unless you have it set up to pull the elevators up a little. I have made gliders like this, modeled after the F-14, decades ago. In reality, if it is a glider, you are best off setting it up for the wings in a fixed position. if you want a glider that hangs in the air, go for the wings out, if you want to throw something that goes like a dart, wings in. If you really want something that goes like a dart, try making a strong nosed F-104 glider. Everyone I have ever made flies incredibly fast. SR-71 shaped gliders, if the front body side chine is done well, make some of the best gliders I have ever made.

    In any event, the center of lift will cause the most problems, which is why I suggested a sliding weight to change the center of gravity, since center of gravity/center of lift are related, but it is not a linear event, and making and figuring out such a system for a glider will be quite a project. Also, I see people post that they get 45 feet or so out of a glide (usually posted as 15 meters, and usually an Ojimak model), I personally always go for the couple of 100 feet, and a rubber band launch, so it depends on what you are trying to achieve. :)
  11. freddyman

    freddyman newbie

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    I'm not going for some crazy far glider. i lost too many planes in trees and my roof to learn that lesson.i just want something that will at least glide 20 ft+ so it won't get stuck anywhere and continue to impress my Friends.
    (p.s, my semi scale f-22 flew 125 ft across my yard and landed on my naihbors home)
    freddy
  12. Zathros

    Zathros Guest

    like I posted before, I can easily make the wings with the gear for you. If you send me a P.M., we can exchange e-mails and you can send me the data so I can make the wings for you. I make a lot of parts for people, and I don't charge or expect anything in return.:)
  13. freddyman

    freddyman newbie

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    thanks zathros, but i have special news. i got the swing wing to work. i plled up a site about gears and pinted some.after finding the center like you told me,i thickened the gears with cardboud and now it is smoth and reliable.i will soon transfer it to the tornado very soon
  14. Zathros

    Zathros Guest

    Great news! I thought you would figure it out. I look forward to seeing this, please, please, post build pics!! :)
  15. freddyman

    freddyman newbie

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    i know i keep saying this but i will try. money is not good so far but i promise to post pics of my plane
  16. Zathros

    Zathros Guest


    Money is affecting all of us! I have yet to meet the Mitt Romney of paper modeling! :)
  17. Willja67

    Willja67 Member

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    You might check this thread out.
  18. freddyman

    freddyman newbie

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    amazing looking profile jet. i apiciate the thread but i just finished the prototype tornado.next is the painted,full cotpit one with a possability of added missles. the thread though could go usful if i try another aardvark.
  19. Zathros

    Zathros Guest

    What a beauty, it sure picked up speed when the wings were retracted! :)
  20. freddyman

    freddyman newbie

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    i misinterpet the gliding performence of the plane. it flew 50 ft across my yard in a windy day. also the tornado can fly well in both transitions.its a bit pitchy with wings spread, but can maintain a short, nice glide unlike my reasent f-111