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Unread 19-05-2014, 11:23
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Re: Turns out Helical Beam Couplers aren't meant to handle that much stress . . .

Quote:
Originally Posted by FrankJ View Post
Flexible couplings are meant to transmit torque, not to hold things in alignment.
Well, I specifically chose Helical over a Lovejoy or Oldham for their ability to both transmit torque and hold things in alignment. I think that the huge amount of angular force and resonance was simply way more than it was intended to handle.

Quote:
To help with the resonant frequency and the vibration, cut off the extra length of screw since it is mass whipping around. Use a a speed controller on the motor to slow the screw down. The more it extend, the faster it can go.
Unfortunately we only have an inch or two of extra length, we cut it about as short as we could get it while still allowing some length in case the ball holder extends past our hard-stop.
As far as speed control, yes it is on a Talon but we already have it as slow as it can go before it starts failing at its extreme down position. Any slower and it stops having the power to lift back up to a Hold position.