Aluminum Plate Engineering/Forming Question

Discussion in 'Aircraft Design / Aerodynamics / New Technology' started by Victor Bravo, Sep 16, 2019.

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  1. Sep 20, 2019 #81

    BBerson

    BBerson

    BBerson

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    A hoop gear from wheel to wheel isn't the lightest and requires a blank about 10 feet long that's hard to find and ship.
    A single short slab like the Cessna/Citabria/Grob/RV just slips into a socket. A single slab of 6"X 3/4" x48" can be sawed lengthwise into both the 4" X 2" gear legs with no scrap. The hoop gear has considerable scrap. The internal socket and truss would require fabrication.

    And how does a ring hoop gear attach to a flat 701 belly?
     
  2. Sep 20, 2019 #82

    pictsidhe

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    Hoop gear is easier to mount and should be lighter without the mounts that seperate leg gear needs. It does indeed have more scrap.
     
  3. Sep 20, 2019 #83

    BBerson

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    How do you mount a circular gear to a flat bottom? A 3/4" solid beam gear across the fuselage is heavier than a deep truss of the same strength. Also is better crash structure.
     
  4. Sep 20, 2019 #84

    Victor Bravo

    Victor Bravo

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    Look at the sketch I posted. (LTFS ????)

    FLAT across the bottom of the fuselage, then large radius down to the gear.

    BB I am not going to be redesigning the 701 fuselage for a Cessna style gear. Been there, done that, got the bankruptcy :)
     
  5. Sep 20, 2019 #85

    flyboy2160

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    :) VB, Man Up! Build your own HT oven!
     
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  6. Sep 20, 2019 #86

    BBerson

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    The sketch in post 29 is not to scale, the curved one needs longer length. (more weight and looks goofy)
    It could be curved more like post 33 even on a flat bottom belly.
     
  7. Sep 20, 2019 #87

    BBerson

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    As a roller owner, I can say that you can't roll to the end of the part. If you want a radius to the end you need a long piece to roll then cut off the ends.
     
  8. Sep 20, 2019 #88

    Winginitt

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    I know you like to innovate. I'm wondering if something smaller than the Storch gear setup couldn't be made for a tri-gear and mounted in the same rear location on the fuselage. I'm thinking something like a small A frame assembly with a long stroke/adjustable coil over shock. I don't mean long stroke like a storch, but more like a conventional street rod shock. You can buy different wt springs and even adjustable valving. If you had something with a 4" stroke, by the time the arc of movement is extended to the wheel, you could have 6 or more inches of travel. If you perfect something, it might become the norm for others. Its not just about the ability to absorb impact without bending, but to disipate it safely. More and more STOL aircraft are showing up with these extended travel landing gears. Here are pictures of a few gears. One is the Aussy Hornet....there is even a Cub. 100_3778.jpg 8-12-15-BNP-0815-Tundra-500.jpg Cub Crafters landing gear.jpg Shock Cub.jpg
    I think the Cub looks great with that gear.


     
    Last edited: Sep 20, 2019
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  9. Sep 20, 2019 #89

    BBerson

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  10. Sep 20, 2019 #90

    proppastie

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    perhaps you have a link or photo?
     
  11. Sep 20, 2019 #91

    rotax618

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    3C8E9943-D391-4C4C-B282-FCC005A60D62.jpeg I’m not at the hangar at the moment, but this is what I used to form a 701/Savannah UC, 16 ton pipe bender.
     
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  12. Sep 20, 2019 #92

    Winginitt

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    and another idea;

    actual landings...no bounce
     
    Last edited: Sep 21, 2019
  13. Sep 21, 2019 #93

    mcrae0104

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    VB, check with Mike Patey. I bet he could sell you a great set of used trailing link mains cheap.
     
  14. Sep 21, 2019 #94

    Sockmonkey

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    How do the stresses work out if you make it in two parts and mount it like so?
    [​IMG]
     
  15. Sep 21, 2019 #95

    proppastie

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    Hint.....should you decide to bend there are issues of the exact bend radius at the neutral bend axis......that is the axis you calculate from/for to figure your exact lengths....You will need to bend some test pieces and meassure what the inside radius actually is in order to know your neutral bend axis (with a large radius that should be T/2 + inside radius). often with a single bend you make the piece oversize and trim after bending.
     
  16. Sep 21, 2019 #96

    Victor Bravo

    Victor Bravo

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    This airplane is going to be using EITHER a one piece bent aluminum gear, or a one piece carbon gear, or a two piece bungee gear. NOT redesigning the fuselage for Cessna gear, or an RV rod gear.
     
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  17. Sep 21, 2019 #97

    Topaz

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    Although I'd pay a large sum to see that, and make an even larger fortune by posting the YouTube video. :D
     
  18. Sep 21, 2019 #98

    wsimpso1

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    Done correctly, the stresses are high everywhere on a max sink rate landing. That is how you make these things reasonably light.
     
  19. Sep 21, 2019 #99

    pictsidhe

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    Thats probably the best way to use two part gear.
     
  20. Sep 22, 2019 #100

    proppastie

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    how accurate do you need the center section distance,.....you can have the each end longer and trim...
     

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