Setscrew in chuck to hold chuck on spindle?

Discussion in 'Newbie' started by Jesse Tutterrow, Oct 31, 2017.

  1. Fadi Zeidan

    Fadi Zeidan

    Joined:
    Jul 5, 2016
    Messages:
    183
    That could be it, was first time using hollowing system. I paid a lot more attention on the second hollowing form to make sure I was at center and did not have a problem. I was paying more attention because it was shallower (5” deep and could see the bottom plus wider opening).
     
  2. Fadi Zeidan

    Fadi Zeidan

    Joined:
    Jul 5, 2016
    Messages:
    183
    No it was in the middle of hollowing, the whole piece started wobbling so I turned it off and had to tighten it again. Got lose one more time so I used the set screws to make sure it stays on. I was doing a 9”x3.25” top, 2.5” bottom.
     
    odie likes this.
  3. Michael Mills

    Michael Mills

    Joined:
    Oct 30, 2008
    Messages:
    26
    Not saying it is the case but could there be a miscommunication?
    I have seven Nova chucks and none came with a washer to use to tighten the insert to the spindle.
    However, they all came with a washer (very small leather) used with the setscrew in the chuck body when securing the insert into the chuck itself.

    I have heard of folks using lead shot or brass (BB) when securing the insert to the spindle to prevent damage to the spindle thread.
     
  4. JeffSmith

    JeffSmith

    Joined:
    Aug 6, 2009
    Messages:
    135
    Location:
    Lummi Island, WA
    I prefer to hollow a lot of things in reverse - the set screw becomes necessary. As has been mentioned, McMaster Carr sells the brass and nylon tipped set screws. They're pretty cheap and protect from thread damage - I bought a couple dozen and slowly changed out nearly every screw as I use them...
     
  5. Dean Center

    Dean Center

    Joined:
    May 4, 2010
    Messages:
    455
    Location:
    Bozeman, MT
    Perhaps the OP is referring to the approx. 1/8" diameter disc that is used between the bottom of the set screw and the metal threads of the spindle, and not a washer at the shoulder on the headstock. Nova chucks come with these little discs, which are designed to protect the threads from tightening the set screw as Gerald commented. They're very easy to overlook or lose and when I did so, I made a new one out of gasket material. (cut with a used .22 cartridge if I remember correctly) They are also supplied in a Nova chuck small parts kit that includes replacement jaw screws. (which also like to disappear)
     
  6. Zach LaPerriere

    Zach LaPerriere

    Joined:
    Apr 1, 2015
    Messages:
    387
    Location:
    Sitka, Alaska, United States
    Home Page:
    I agree: nylon washers are UNSAFE unless you use a set screw.

    Here's my horror story. Craft Supplies gives a free nylon washer with every chuck sold. So after turning seriously for perhaps six months I thought: might as well put on a nylon washer. All was well until I had a larger heavy bowl reversed on the megajumbo jaws. This was a couple years back, so I don't remember the details...but the whole thing unscrewed itself and landed still spinning on the shop floor.

    The bowl was ruined, the Mega jumbo jaws were bent, and I would have been hurt (possibly seriously) if I was in the line of fire.

    Conclusions:
    1. Do not use a nylon washer unless you also use a set screw.
    2. Seat the chuck on the spindle by hand, spinning with a small amount of momentum.
    3. This is important: For heavy work, if you don't use a set screw—Keep your tool rest close enough to your work that it would stop a heavy piece from unscrewing.

    I've never had a piece unscrew since since. Thankfully my local machinist let me use his hydraulic press and I was able to right the mega jumbo jaws to within acceptable tolerances.

    --And if anyone wants a nylon washer or two...I have a half dozen or more still in the package. ;)
     
  7. Bill Boehme

    Bill Boehme Administrator Staff Member

    Joined:
    Jan 27, 2005
    Messages:
    8,122
    Location:
    Dalworthington Gardens, TX
    Home Page:
    Bending cast aluminum isn't good ... bending it back can be scary because of the risk of work hardening.

    I have several additional washers that I can contribute. The good news is that they are useful for shimming a short table leg.
     
    Zach LaPerriere likes this.
  8. Mike Johnson

    Mike Johnson

    Joined:
    Jul 26, 2016
    Messages:
    616
    Location:
    Nebraska
    If you don't tighten the lug nuts on your vehicles wheel it will also fall off when you least expect it.
     
  9. Zach LaPerriere

    Zach LaPerriere

    Joined:
    Apr 1, 2015
    Messages:
    387
    Location:
    Sitka, Alaska, United States
    Home Page:
    You're absolutely right, Bill. Thanks for pointing that out. I ran it past two seasoned machinists, so the small amount I tweaked it back got the okay, but if it was much, it would be best to go straight to the recycling.
     
  10. Bill Boehme

    Bill Boehme Administrator Staff Member

    Joined:
    Jan 27, 2005
    Messages:
    8,122
    Location:
    Dalworthington Gardens, TX
    Home Page:
    That is so true. It almost happened to me once when a shop rotated the tires on my car and forget to put the lug nuts back on one of the wheels. Something felt strange so I stopped to investigate. I "borrowed" a lug nut from each of the other wheels so I could make it back to the shop. They were nonchalant about the whole deal and asked if I wanted them to replaced the missing nuts. :rolleyes: OK, I'll admit it, there actually is such a thing as a stupid question. :D
     
  11. Ely Walton

    Ely Walton

    Joined:
    Mar 23, 2017
    Messages:
    19
    Location:
    Troutman, North Carolina
    Here is the specific brass-tipped set screw I bought to fit my Nova SN2 adapter for 1-1/4x8 spindle: p/n 94085A128 https://www.mcmaster.com/#catalog/123/3073/=1a597ee . The standard screw had the cup point, which made a little mark when tightened. I think the brass tip will still hold and yet not harm the spindle.

    Ely
     
  12. Gerald Lawrence

    Gerald Lawrence

    Joined:
    Feb 6, 2010
    Messages:
    718
    Location:
    Brandon, MS
    I ordered the same ones and got them in Saturday
     
  13. Leo Van Der Loo

    Leo Van Der Loo

    Joined:
    Oct 13, 2016
    Messages:
    199
    Location:
    Rainy River District Ontario Canada
    About the plastic or other material washers used, makes for a good chance you will get wobble or and vibration, WHY ?, well take that chuck and back it off half a turn or so, and then see if you can wiggle that chuck.

    Surprised by the amount you can ??, threads do have and need some room to be able to have spin these pieces onto each other, now when you stick a washer between your chuck and the spindle, that material can will give as it is able to be compressed.

    Now take a metal lathe and install a screw-on chuck, there will be no washers used, and the forces tightening the chuck when cutting metal are a lot higher than on the wood lathe turning wood, and these metal turning chucks all come off just fine every time, I have used and done this enough times to tell you that they do not get stuck, however these surfaces and threads are properly machined, not so much on low cost wood lathes.

    The case about the set screws use on the wood lathes are to be used on spindles that have a groove machined in the spindle just past the threads end, see picture.


    The problem now is that there is no agreed distance of where the groove is, and then we have lathes that do not have the groove in the spindle, but some chucks have the threaded holes and turners now want to use the set screw, even when there is not a good place to screw it down to, the setscrew with soft tip is one way to still be able to use it.

    I have another manner you can use the setscrew, if you are not against making your lathe safer to use, a flat spot ground on your spindle will work, and yes I know the objection to that is, every chuck screw-hole will tighten at a different spot, so you mark that chuck where the flat spot is and drill and tap it where it will screw down to that spot.
     

    Attached Files:

    William Rogers likes this.

Share This Page