1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

  2. Click here to enter the drawing for your chance to win a Kizer Sheepdog & Ka-Bar Dozier Folding Hunter, , Bladeforums.com swag or memberships!

    Be sure to read the rules before entering, then help us decide next week's giveaway by hitting the poll in that thread! Entries close at midnight, Saturday August 10!

    Once the entries close, we'll live stream the drawing on Sunday, July 28 at 5PM Eastern. Tune in to our YouTube channel TheRealBladeForums for a chance to win bonus prizes!

    Questions? Comments? Post in the discussion thread here

Some thoughts on hard Ebonite

Discussion in 'Carothers Performance Knives' started by Nathan the Machinist, Jan 25, 2019.

  1. Nathan the Machinist

    Nathan the Machinist KnifeMaker / Machinist / Evil Genius Moderator Knifemaker / Craftsman / Service Provider

    Feb 13, 2007
    Once upon a time, a long time ago (as in the 1800's, UffDa was middle aged at the time) you could make stuff out of wood, bone, stone, glass and other natural materials. There was no "plastic".


    ebonite.jpg


    Someone recognized there was a need for a waterproof synthetic material to substitute for Ebony for certain applications such as reed musical instruments (think oboe) because ebony was getting spendy and it cracks when it gets wet a lot.

    Someone thought to vulcanize the hell out of natural rubber to make a hard semi-plastic. Like phenolic (micarta) this is an old polymer that crosslinks into a hard thermosetting material, but unlike other hard man made materials it is natural rubber base and is still slightly flexible.

    Real Ebonite like this is not used much anymore at all because it has some real disadvantages compared to modern alternatives such as nylon, Delrin and other modern thermoplastics, though it is still used in musical instruments, pipe stems, and things like some high end fountain pens etc. Applications where cost isn't a driving factor and properties such as tonal or tactile are important.

    Disadvantages:
    It's made of natural rubber, being a natural product there can be inconsistencies such as areas that can look a little splotchy.
    Being real rubber, it does not tolerate ozone or (years of) extended sunlight. It can check and fade over time if it's stored next to an electric motor that generates ozone in use, or kept out in the sun for a long time.
    It's not as strong as some modern alternatives. If you pound on stuff with your handle you're likely to damage it where micarta is tougher.
    It smells a little funny at first because it is highly vulcanized which means a faint sulfur and burnt rubber smell. It's not obnoxious, but if you're accustomed to a highly sanitized scent free world you might not like it.
    It's expensive because someone has to literally go cut and bleed a rubber tree to acquire the raw material. I'm offsetting this expense some for now because this is prototype development work, but you can expect that once I have Ebonite dialed in it won't be cheap.

    Advantages:
    With a much lower durometer than other synthetic materials it gives a pleasantly dead "thunk" in an impact compared to modern alternatives. This is nice in a chopper.
    It has a pleasant smooth warm feel coupled with nice grippy tactile traction like only rubber can give. It is super pleasant in the hand. This is nice in about anything from a chopper to a small EDC and everything in between.


    A long time ago the core of Ebonite brand bowling balls were actually made of real ebonite. They're not anymore, it's polyurethane. But some antique bowling balls were the source of the original Ebonite I used for prototypes. Moving into beta build production I imported Nikko Ebonite from Japan. That's what this is, current production Japanese Ebonite. It's a little harder than the antique ebonite we started with. I have mixed feelings about this.

    Being rubber it benefits from a larger screw head to hold it down, so the Ebonite scales will come with a natural color titanium screw with an oversize head. Nothing fancy.

    Jo uses Ebonite in her competition chopper instead of terotuf or rubber.
     
    Last edited: Jan 25, 2019
  2. mpjustin

    mpjustin Gold Member Gold Member

    806
    Sep 5, 2009
    This is great information Nathan, thank you!
     
    Oyster likes this.
  3. Bulldog18

    Bulldog18 Gold Member Gold Member

    938
    Jan 11, 2008
    Thanks Nathan! Very informative and now I have more choices to consider.:thumbsup:
     

Share This Page