Rubber band chatter reduction

Discussion in 'Tutorials and Tips' started by john lucas, Oct 22, 2013.

  1. john lucas

    john lucas

    Joined:
    Apr 26, 2004
    Messages:
    5,830
    Location:
    Cookeville TN USA
    I was turning more cupcakes today. when I turn standard boxes that are thin sometimes you get chatter out toward the edge when hollowing. On regular boxes I just dampen it with my fingers on the outside. Can't do that with the cupcakes because of the fluting on the outside. I put several rubber bands around the outside and it completely eliminated the chatter so I could get a clean cut on the inside.
     

    Attached Files:

  2. hockenbery

    hockenbery AAW Advisor Staff Member

    Joined:
    Apr 27, 2004
    Messages:
    4,311
    Location:
    Lakeland, Florida
    Home Page:
    Cool idea what made you think of it?

    When I hollow things like a goblet I do the hollowing first and then turn the wall thin from the outside.
    Can even use a light on light woods to show the thickness.

    Have you tried hollowing the inside first with the cupcakes?
    Fluting the last might be a problem with a thin wall even supported from the tailstock with a ball inside.

    Your cup cakes a really nice by the way!
    Al
     
  3. john lucas

    john lucas

    Joined:
    Apr 26, 2004
    Messages:
    5,830
    Location:
    Cookeville TN USA
    If I hollow the inside first I run into the risk of the flutes cutting into the inside. It's hard to get the depth of the V's really precise. someday I hope to add an X/Y axis to the router table to help control the depth. The whole piece also vibrates less when cutting with the router if the piece is solid.
    As far as the rubber bands go I think I heard that one time when discussing turning thin bowls. Don't know where it came from. Just thought I might try it on these boxes and it worked perfectly.
     
  4. Bill Weaver

    Bill Weaver

    Joined:
    Feb 26, 2010
    Messages:
    167
    Location:
    Riverside Ohio
    John,
    Your thought and the principal is correct. A brake drum/rotor lathe used in auto parts machine shops uses a leather or rubber lined strap for the very same reason to eliminate vibration when turning a drum inside or end cuts on a rotor.

    Just thought I would throw that in there for comfort.;)
     
  5. hu lowery

    hu lowery

    Joined:
    Mar 17, 2013
    Messages:
    485
    Location:
    Roseland LA USA
    surgical tubing

    Keeping surgical tubing on hand is convenient for bigger stuff. You can also cut an inner tube in a long continuous spiral and get a long rubber strap. It doesn't take much to dampen vibration when it is first getting started, can be impossible to control once it gets bad.

    Hu
     
  6. Tom Coghill

    Tom Coghill

    Joined:
    Mar 20, 2013
    Messages:
    32
    Location:
    Anchorage, Alaska
    John,

    Great idea - Thanks for sharing!
     
  7. Ian Thorn

    Ian Thorn

    Joined:
    Apr 5, 2012
    Messages:
    161
    Location:
    Mosgiel New Zealand
    That's a great idea thanks for sharing John

    Ian
     
  8. odie

    odie

    Joined:
    Dec 22, 2006
    Messages:
    4,424
    Location:
    Deep in the woods
    There are times when I am unable to use either of my bowl steadys because of flaws, voids, or other irregularities. I'll keep the rubber band idea in mind, and use it when it applies to my particular needs.

    Thanks for adding your ideas, John........:cool2:

    Out of curiosity......I assume your cupcakes are end grain hollowed. What size, rpm, and tool are you using? (Gouge, or scraper) Are you using a variety of wood species, and do you find different species may effect the performance of your methods and tools?

    Most of my work is cross-grain bowls, but I do have occasion to hollow out some small bowls of similar size to your cupcakes. With most work where obtaining a finely produced "tool finish" is necessary before sanding, and eliminating chatter, or vibrations is problematic, I find it beneficial to bring the finished interior wall surface level down gradually in depth, prior to lowering the depth of the rest of the interior. This way, the stabilizing effect of the bulk interior waste wood is used for as long as possible before eliminating it. Any chatter at all destroys an otherwise finely created "tool finish", so your rubber band idea could be used in conjunction with my methods of eliminating as much wood vibrations as possible, through the use of tools and technique. First preference would be to use a bowl steady, but as said previously, sometimes that option isn't available to me. My goal is to eliminate as much sanding as possible, and I will use whatever method or technique I can to get there.

    I can foresee myself using this rubber band idea from time to time.

    (Disclaimer: Because of past input on this forum, I must point out that what works best for me, may not be what works best for everyone else......or, anyone else, for that matter. First class results are the ONLY thing that count, and there is often more than one path to that final destination.)

    ooc
     
    Last edited: Oct 26, 2013
  9. john lucas

    john lucas

    Joined:
    Apr 26, 2004
    Messages:
    5,830
    Location:
    Cookeville TN USA
    I hollow with either a bowl gouge or detail gouge. On larger pieces i thin a little at a time but on small boxes I usually hollow as I go and then make a clean up pass with a Hunter #4 or #5 so I don't have to sand with any course grits Its that last pass when the chatter developed. The hunter cuts as a be el rubbing tool on the bottom and shear scrape up the sides It's the difference between the super clean bottom and less clean sides that I have to sand at all. I usually just hit it with 600 grit to even out the sheen
     

Share This Page