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

Hidden tang strength

Discussion in 'Custom & Handmade Knives' started by Evan.S.Merritt15, Nov 30, 2018.

  1. Evan.S.Merritt15

    Evan.S.Merritt15

    31
    May 11, 2018
    I’ve seen many people make hidden tang knives and I see them make a handle by puttin a hole in a piece of wood, pour epoxy into the hole, and put the tang in the hole. Wouldn’t it be better to put epoxy and maybe a pin or two in the handle or does epoxy make a strong bond?
     
  2. Salem Straub

    Salem Straub KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    Oct 20, 2008
    Hidden tang knives can be very strong... but there are a lot of details to get right for that to happen.
    The tang dimensions have to be stout enough and of acceptable length.
    The tang shoulders at the ricasso have to have at least somewhat rounded inside corners, no stress risers.
    The heat treatment needs to be spot on. The tang will be better off, generally speaking, if the temper is drawn back to a springier state where it passes into the handle.
    The tang must be freshly abraded for some tooth, and perfectly clean, before epoxy is applied.
    The handle block must have any dust blown out of it... if the wood is very oily, an acetone treatment slightly before glueup can improve epoxy bond.
    Often the tang will be lightly notched if no pins are to be used, to give the epoxy additional features to grab onto.
    Epoxy must be applied to all surfaces before assembly, and there should be no air pockets.
    A high quality adhesive must be used.
    If these basic conditions are met, a hidden tang handle with no pins can certainly be strong enough that only destruction of the handle material will be enough to loosen and remove the handle. To me, that is the mark of "strong enough."
    If the handle is strong enough, then other design consideration come into play... such as, how will handle construction affect balance? Is it preferred to be able to see the handle material all the way around the grip, uninterrupted by tang metal? If carbon steel, do you want exposed tang metal in constant contact with skin oils and other corrosive influences? Do you want all the exposed glue joint of a full tang knife, acting as a potential way for moisture to work in under the scales?

    And so on. That's my take, anyway!
     
    Shaw Blades, Natlek, shqxk and 8 others like this.
  3. Evan.S.Merritt15

    Evan.S.Merritt15

    31
    May 11, 2018
    Okay cool. I saw a knife blank with a hidden tang that I wanted but didn’t know if I should drill a hole and put a pin in.
     
  4. Lorien

    Lorien Moderator Moderator

    Dec 5, 2005
    regardless of outcome, putting a pin in there will be a good lesson.
     
    Chris Montgomery and john april like this.
  5. Chris Montgomery

    Chris Montgomery

    Dec 8, 2011
    I always like to see a mechanical connection, pin through or threaded to the tang. Modern adhesives are amazing, however trusting just epoxy is not what I like to see.

    Chris
     
    Scott Hanson and Cvrobinson like this.
  6. Kevin Jones

    Kevin Jones

    Oct 28, 2006
    I prefer a pin or pins as well from both structural and aesthetics perspectives.
    A properly placed and well executed pin/pins can actually add a little pizzazz to a otherwise plan handle.
    "Hidden" pins are also used on occasion.
     
  7. daizee

    daizee KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    Dec 30, 2009
    Nice summary, Salem, thank you.

    I've taken to drilling a few shallow divots (less than width of chosen drill bit) in the flats of my tangs if I'm not going to use a pin (and even if I AM in a burly blade). It strikes me as less likely to compromise the strength of the tang while serving the same purpose.
     
  8. mete

    mete Gold Member Gold Member

    Jun 10, 2003
    In Viet Nam our Huey Helicopter rotors were put together only with adhesives ! these of course were special industrial grade types Never use 5-10mnute epoxies for anything ! Clean surfaces carefully , follow instructions and you;ll have a strong , long lasting joint.
     
    Natlek likes this.
  9. Natlek

    Natlek

    Jun 9, 2015
    Pin......................what kind of help would be on hidden tang knife ? I can t see what would do that pin ? To stop tang to pull out of wood ???? Will stop side forces on wood/handle maybe ?
     
  10. bccustomknives

    bccustomknives

    174
    Jan 11, 2014
    ever seen a katana ?
     
  11. Natlek

    Natlek

    Jun 9, 2015
    Yes ?
    Well, that exactly make my point :) If that one pin can hold that long katana handle , imagine what can epoxy do in perfectly prepared tang and wood ?
     
  12. shqxk

    shqxk

    Mar 26, 2012
    I always prefer the cleanness and balance of well made pinless hidden tang handle.
     
  13. Scott Hanson

    Scott Hanson KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    Sep 6, 2014
    I make a lot of hidden tang Scagel style knives, and even as good as adhesives are today, I still pin all my handles. I think a mechanical method such as an addition of metal pin stronger than a chemical/glue securement by itself. IMHO a pinned handle has always been the traditional way of securing a handle on to a hidden tang knife, and I think a Scagel style knife looks naked without a pin.
     
    Natlek likes this.
  14. bccustomknives

    bccustomknives

    174
    Jan 11, 2014
    wanna see what it can do? Try leaving it on the dashboard in your car on a hot summer day,or on the bed of a truck lol...epoxy and heat don't mix well,that's why a mechanical fix (on top of glue) is a must...I'll quote the late Keith Spencer..."a glue only construction is just not good enough.period"
     
  15. Natlek

    Natlek

    Jun 9, 2015
    Really ?
    Call me back when you make mess with some handle and you must remove it ,on hidden tang knife of course ....and try with heat to lose handle :D My friend , most epoxy can withstand at least about 140 Celsius degree........
    On knife below on the picture/Micarta handle / when I assembling /gluing handle I make mistake ....there was are small gap between Micarta and stainless ........do you wanna see my industrial heat gun ????????????? Don t help at all ! I destroyed handle mechanically and even that was not easy .......
    Hey , pin look so good on handle , so if someone like it go for it .Of course that pin will add additional strength to handle but don t tell me that without pin handle will fall apart :p
    [​IMG]
     
    Last edited: Dec 4, 2018
  16. bccustomknives

    bccustomknives

    174
    Jan 11, 2014
    well,to each their own,i personally will continue to use pins...as for your industrial heat gun on a micarta handle,after you took it apart,have you noticed how the epoxy looked,all brown and crumpled? Imagine several heat cycles like that after exposing it to the elements (hot cold,moisture,stress) plus the natural tendency of wood to shrink and expand and you have a more or less guaranteed failure down the track,even if it might take a while...I have seen it happen
     
  17. mete

    mete Gold Member Gold Member

    Jun 10, 2003
    I have a couple of rifles bedded with Acraglas and 40 years later it's like rock. Get high quality epoxy , apply it properly and it should last many years !!
     
  18. john april

    john april KnifeMaker / Craftsman / Service Provider Knifemaker / Craftsman / Service Provider

    Feb 27, 2006
    bill bagwell made many bowies without a pin, and i have never heard of one coming apart. personally i like a mechanical fastener the customer can see, and for my peace of mind. i used to collect old 1800's knives, back then they used something called cutlers cement, which was beeswax mixed with brick dust to bed hidden tangs. many used no pin.
     
  19. mete

    mete Gold Member Gold Member

    Jun 10, 2003
    " Epoxy Performance " This forum had in the past a number of excellent threads of various epoxies - very informative . maybe it's time to bring them back.
     
  20. Juha Perttula

    Juha Perttula Basic Member Basic Member

    173
    Mar 27, 2013
    I prefer hidden tang because it generally looks better. I grind some slots into the tang and then epoxy. Then the blade does not come away without breaking the wooden handle.
     

Share This Page