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Question Linear Actuator BK or Thrust Bearing?

Discussion in 'DIY Motion Simulator Building Q&A / FAQ' started by F1 Guy, Jan 31, 2018.

  1. F1 Guy

    F1 Guy New Member

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    Hi all,
    I took a quick look around the FAQ and didn't find anything on this. What is the best option for a ball screw linear actuator's drive side bearing?
    I'm wondering if builders are using the standard ball screw BK end piece or some other custom thrust bearing or axle type tapered roller bearings to handle the high loads. I might be over thinking it, but it seems like the high vertical loads can cause the BK bearing piece to pop out or fail.

    Thanks
  2. Ads Master

    Ads Master

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  3. adgun

    adgun Active Member

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    Inside a BK bearingblock sits a double row angular contact bearing
    Those can handle axial and radial forces
    Regards Ad
  4. F1 Guy

    F1 Guy New Member

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    Thanks for clearing that up.
  5. Bord-Ing.

    Bord-Ing. New Member

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    As a rule of thumb, a small ball bearing (up to 12 mm iD) can handle up to 25% of the radial dynamic load. Let's take a standard 6000 bearing (10 mm iD, 26 mm oD). It has a radial
    dynamic load rating of 4850 N, so it's axial load should not exceed 4850 * 0.25 = 1212 N. This is the same as 123 kg or 271 lbs here on earth. Not so bad ;)

    Begining with a iD of 12 mm or bigger, the axial load can be 50%.
    • Informative Informative x 1
    Last edited: Feb 3, 2018
  6. F1 Guy

    F1 Guy New Member

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    Awesome detail. Thank you for those numbers.
    Now I'll know how close or far I am from those max loads.
  7. adgun

    adgun Active Member

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    A BK12 bearingblock can handle 5900N static axial and radial load, and 10400N dynamic load