Acceptable chuck runout

Discussion in 'Tutorials and Tips' started by musky, Sep 22, 2007.

  1. Steve Worcester

    Steve Worcester Admin Emeritus

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    If you leave the set screw unfastened, that problem will remedy itself after you start turning as the chuck will snug itself up (just don't reverse the lathe)
     
  2. waltben

    waltben

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    I had a lot of runout (didn't have a micrometer, but it was quite visible) in a new chuck many years back that turned out to be the spindle adapter. The seller sent me a new adapter as a first fix and that did the trick. Some time after that, I began using nut and washer welded up faceplates for jigs and other odds and ends instead of costly machined ones. Since these are almost never true (and need spacers), I had to live with wobble - but quickly found that once I turned a tennon or jig, it didn't matter. Only issue is if I take one off and later put it back on a lathe - I've got to true it up again. Chuck runout can only affect a piece that you've turned the outside of a piece with a socket or tennon and then reverse to find it wobbles. I've one set of jaws out of eleven that I can't seem to ever get completely right. I'm not even certain if I didn't cause the one set to be out of true myself, but I reserve them for pieces that wobble won't matter.
     
  3. KEW

    KEW

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    A little side-note:
    I believe what you are saying is true for any current lathe, but my Powermatic 90 has a 1-1/2" long spindle and the "original" Nova chuck I have does not have threads that deep. it references off of the nose of the spindle. The Stronghold Taperlock threads run all of the way through and it references off of the shoulder like most lathes. Both run true.
     
  4. john lucas

    john lucas

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    Kurt I have that problem with my Powermatic 3520. They made the spindle a little longer so that they could add set screws to the faceplates. For several of my chucks and some of my faceplates I need 2 nylon washers or my homemade metal washer to that it bottoms out like it should.
    If your lucky and the chuck runs true by bottoming out on the face of the spindle then that should work. That relies on the face of the spindle being true and also the inside of the chuck. Since these weren't designed as the registration surfaces they may or may not work.
     
  5. MichaelMouse

    MichaelMouse

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    You can get the "L" insert for Novas which is longer and has the spot for a grubscrew if you get tired of washers.
     
  6. musky

    musky

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    chuck runout

    Just a followup to everyone. I called Oneway yesterday, and there answer was that .004 was fine, but they would like to see it closer to .002. They suggested putting a piece of hardwood to the face of the chuck in the high spot, and giving it a rap with a hammer to help seat the taper adaptor. Made me a little nervous when doing it, but what the heck, they suggested it. After doing this, I retorqued the screws, and checked the runout. It is now slightly less than .003, time to start turning. Thank you to all for your suggestions.
     
  7. Steve Worcester

    Steve Worcester Admin Emeritus

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    bump to resurface
     
  8. Ed Davidson

    Ed Davidson

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    If you have a bad chuck induced run-out problem, there is a tool that will dial in your chuck to absolute zero run-out. The modern version of this tool is called a Leveling Chuck, made by Lindow-White, and is intended to be used by rose engine operators, where high precision is required.

    Besides the chuck, you'll need a gage on an articulating arm, like this MSC model - I got one just like it on eBay for $45.

    I've also used my leveling chuck on a conventional lathe for offset (elliptical) turning as well - it's heavy duty and highly adjustable. BTW, I have no business affiliation with L-W.
     
    Last edited: Nov 24, 2009
  9. rsser

    rsser

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    If you measure say 6 thou of variation that's really only 3 of run-out, and if it's coaxial it's no drama anyway.
     
  10. Steve Worcester

    Steve Worcester Admin Emeritus

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    With ".006 runout, I would feel is so little as the wood willl move more than that as you turn.
     
  11. Richard-tx

    Richard-tx

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    Care to explain that? I am unsure what you mean.
     
  12. Steve Worcester

    Steve Worcester Admin Emeritus

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    The wood, even if bone dry, will likely move more than that amount while you are turning. It is due to not only loss of moisture, but to relieving of the stress in the wood. So even if the chuck is dead on, there will always be movement in the wood during the process.
     

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