Folding Props

Discussion in 'ALTA' started by Zac Eskelsen, Jun 18, 2015.

  1. Zac Eskelsen

    Zac Eskelsen New Member

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    In the past I've had issues with folding props and not being able to get out all the vibrations because I wasn't able to balance the props.
    So I guess my question is, how do you balance folding props and minimize those vibrations?
     
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  2. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    If you use something like a Top Flite or DuBro Tru-Spin prop balancer, do you find that you cannot keep the blades unfolded?

    Andy.
     
  3. Zac Eskelsen

    Zac Eskelsen New Member

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    I use DuBro. but the folding props i've used in the past don't have a hub so its not like you can mount it on the balancer. I've gone as far as making a hub, but if the props fold in or aren't perfectly straight then its not accurate.
     
  4. Andy Johnson-Laird

    Andy Johnson-Laird Administrator
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    I suspect we'll need to 3D print some kind of clamp that holds the blades in position -- the ALTA's blades fold in the horizontal plane -- which was your point in the first posting. The 3D clamp would need to pretty precise otherwise it would cause a potential imbalance itself.

    Andy.
     
  5. Gary Haynes

    Gary Haynes Administrator
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    Zac I'll go out on a limb and say that the Alto test pilots are not doing any balancing. I've not heard of anyone doing balance on any carbon props and some folks that I respect didn't even balance their wood props and had no vibration issues based on their tuning of the vibration dampers. And those were pre-MoVI.
     
  6. Zac Eskelsen

    Zac Eskelsen New Member

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    Interesting. Its difficult to not want to balance the props. But I suppose if you aren't getting vibrations you shouldn't need to worry about it.
    I've heard that weighing each prop with a precise scale and getting the weights equal was another option.
    any opinion on that?
     
  7. Aj White

    Aj White Member

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    I havent bothered with balancing props for about a year, ever since I just started buying quality CF props. I spot check every once in a while but they are almost always perfect. I'm sure FF is doing the homework and wouldn't provide sub-par props on the rig.

    The thing is, we are all so used to tinkering and "fixing" stuff. The whole goal with the ALTA is to change that frame of mind and just plug and fly... focus on creativity!
     
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  8. Janne Hoglund

    Janne Hoglund Member

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    I balance every prop I use! Even if they only make very little vibrations why not get rid of it by balancing them ;-)
    What I can say is that, most often, the more monney you spend on props the better balanced they are.
    For every Okto of mine i usually get 10-12 props. Of 12 plastic props, 12 always need balancing. With 12 expensive Carbon props usually 2-4 dont need any balancing at all, and the rest need a lot less than the plastic ones.
     
  9. Angus Benson-Blair

    Angus Benson-Blair Active Member

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    For folding props, get a jeweler's scale and then add weight to the lightest blade at its center of gravity. It's what most people do who fly single rotor helis which use effectively the same thing ie two folding blades.
     

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