Coaxial Cinestar...

Discussion in 'Cinestar Misc' started by Benjamin Rowland, Jan 26, 2013.

  1. Alex Smart

    Alex Smart Member

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    So Brad,
    see you ve been playing around quite a bit..
    What do you recon is best for heavy lifter in coax, a X8 lets say like your set up with WKM or a dodeca with standart MK gear?
    Regards,
    Alex
     
  2. Michael Braun

    Michael Braun Member

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    How do you mount bottom motors on coax?
     
  3. Brad McGiveron

    Brad McGiveron Active Member

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    Depends on what weight you looking to lift?

    I like both but the lack of ultra heavy lift power options for MK makes the WKM for me a better option currently.
    Given a smaller payload they both are good.


    Just take the QC motor mount and put them on the bottom side of the clamps as well. You'll need slightly longer bolts like the ones that are used on the center frame. Take out the press nuts on the bottom(or top) mount.
    Basically one mount on each side of the clamps.
     
  4. Bryan Harvey

    Bryan Harvey Member

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    Brad, what kind of flight times do you get on your 4s WKM X8 lifting the Canon 5dM3? Could you fly the Epic with 4s also? Which motors/ESC's are you using on this setup?
     
  5. Brad McGiveron

    Brad McGiveron Active Member

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    Oh the 4s X8 I posted here is stock MK driven and will do about 8 minutes on 2x6200 4s quadropowers with a 5DIII. More like 10 minutes or more with the GH3. I don't run my lipos very low so you can probably improve on those times if your willing.
    Ummm... you could maybe lift an Epic but it would be at its absolute limits and overheat and handle very poorly. That is stock QC motors with a CS6 center frame and booms. A mishmash PS1 gimbal and gear.

    The WKM one i posted recently is 6s only and pretty much lifts just about anything comfortably. Not to mention, the more power you have the better the lighter cameras will fly as well. It's too heavy for 4s or at least at the C rating of my current QC lipos.
    You could series the 4s together and run at 8s as long as you regulated the power to the WKM or MK stack.
     
    Bryan Harvey likes this.
  6. Dejan Mugosa

    Dejan Mugosa Member

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    HAHAHAHA we started a revolution with this coax :)
    Well if i got 1 $ for each happy face after conversion i could go on vacation.
     
  7. Bryan Harvey

    Bryan Harvey Member

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    I'm excited to try, but if you read through this forum, most people who tried it say the opposite about coaxials. Less stable, worse in wind, with aerodynamic explanations of why. What has changed in the technology since then?

    http://www.rcgroups.com/forums/showthread.php?t=1484076
     
  8. Dejan Mugosa

    Dejan Mugosa Member

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    Nothing has changed. They just did not set it up right or used the right prop configuration. The difference is 80% in how stable it is. And belive me i built about 20 off them, not one.
     
  9. Alex Smart

    Alex Smart Member

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  10. Howard Dapp

    Howard Dapp Active Member

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    I'm here to stand by my decision to switch to coax. I flew with it on a gig for the first time over the weekend and wow it's soo much more stable, even my cam guy immediately said it was more stable on the first flight....in both the calm and wind. I'm very impressed.

    In that RCG link most of those guys are talking about the Y6 config...I always read that Y6 wasn't as stable a X.
     
  11. Howard Dapp

    Howard Dapp Active Member

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    Alex, what's your config? motors, esc, props? I know you're using MK. What's your AUW?
     
  12. Dejan Mugosa

    Dejan Mugosa Member

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    • Well need a lot more info on , motors, electronics, .... since then i can give advice.
    • Same propelers only aplays on DJi. For MK if he has same props without some serius mixer changes you have yaw problems.
    • Also if the motors and props are not 100 in line then you can get funny results. But this goes for all kopters.
     
  13. Howard Dapp

    Howard Dapp Active Member

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  14. Alex Smart

    Alex Smart Member

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    AUW is 4kg.
    I m using MK stack, so 3638 motors and latest FC and Bl boards.
    The configuration is X8, on the mixer side Im using QUAD X with 4 extra motors, uper ones at 61, lower ones at 71%.
    Props 1365 CF up and down.
    The strange thing is that It was real good on the first flights but the third time I took it out it was acting weard,Im doing a general revision and for now I would like to change the props as theres a few that are not tracking good, they are cheap ones from foxtech..
    Any tips on props and general configuration woulld be great!
    Many thanks
     
  15. Howard Dapp

    Howard Dapp Active Member

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    That's a light setup.
    Swap your props for Xoars, much better performance from them.
    Are you running 4s or 5s?
     
  16. Alex Smart

    Alex Smart Member

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    Runing on 4s,
    What props would you recomend then?
    1365 Xoar up and down?
     
  17. Dejan Mugosa

    Dejan Mugosa Member

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    For 13x6.5 the best performance is 64%, 72%. And ofcourse xoar. But i can say that for kw4, for 3638 should be close or the same.
    propelers need to be totaly centered.
     
  18. Alex Smart

    Alex Smart Member

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    Thanks Dejan!
    On the other side, I see some people with coaxials have all top motors CW and bottom CCW,
    what do you guys think about that?
    Regards
     
  19. Pavlos Antoniou

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    it depends on the controller..! For instance HFP says top motors cw and bottom CCW>.. The most efficient is the other config ...! that are mixed on top and bottom.!
     
  20. Dejan Mugosa

    Dejan Mugosa Member

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    Well Mk to cw and botom ccw is much better. DJI and HFP have original mixer top cw and bottom ccw but we have made new mixer for dji to be the same as mk. I like it more but i dont see any big difference.
     

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