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  1. #1
    Less than 10 posts so far!
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    Unhappy Lift problems

    I have just built an eagle 1 with a 600cc 4 cylinder bike engine , it has a 900mm 9 blade fan with a 45 decree pitch. Had a test run last night , front end lifted at about 8500RPM (engine ) but back end lift and thrust at about 10500 (engine screaming) if I increase the pitch would it give more lift and less revs, Can anyone help.

  2. #2
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    Default Re: Lift problems

    Sounds to me that you go a ratio problem, with that amount of pitch on the blades, the engine should not be able to rev that high. Any pictures available?
    In the beginning there was the Cube; I know where is came from and it has the power to create Hover life. But with great power comes great Fun.

  3. #3
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    Default Re: Lift problems

    Quote Originally Posted by atters View Post
    Sounds to me that you go a ratio problem, with that amount of pitch on the blades, the engine should not be able to rev that high. Any pictures available?
    I have attached two pictures, I sent all the info for the gearing of my engine to Ken at K&M Products and he sent me all the parts required and told me to run it in third gear, I tried 4th 5th & 6th gear but not much better.
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

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  4. #4
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    Default Re: Lift problems

    If your splitter plate is correct and you bulit the hover to the plans, then I agree with Atters, it must be a gearing problem. How many teeth does your belt pulleys have on them (drive & driven)?

  5. #5
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    Default Re: Lift problems

    Thanks guys, I have just spoke to Ken and it looks like I've set the pitch all wrong, I will try it tonight and let you know how I get on, sorry for wasting your time, "novices" who needs them ?

  6. #6
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    Default Re: Lift problems

    Novices! The Club needs them. Never be afraid to ask.

    Jim

  7. #7
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    Default Re: Lift problems

    Hi,
    A 900 mm 9/9 at 45 will absorb 51 Kw at 2500 rpm (+/- 70 HP).
    If your engine developpe such power, you must use a ration like 3.4 (2500 rpm on fan and 8500 rpm on engine).
    Have you try a lower pitch ?

  8. #8
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    Default Re: Lift problems

    Thanks for all your comments

    Had a go last night at re-setting the pitch,(Grinding in hub bearings) not good ! Will replace before next test, When I spoke to Ken he said there are four dots on the root of each blade 10 degrees to 50 degrees, Line the blades to 45 degrees inbetween the 40 & 50 dots with the split in the hub, is the 50 degree dot nearest the leading edge ? I've been looking for a diagram online to see how to set the pitch but can't seem to find one.

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