Leather Tear Test - looking back on old mistakes

Discussion in 'General Slingshot Discussions' started by Jeb, Dec 12, 2015.

  1. Jeb

    Jeb Baba Hunter

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    Most old hats will certainly already know to consider this but it may not be obvious to folks just starting out. It wasn't to me.

    A while back, just after I started making my own bands, I had some serious trouble with leather pouch failure. Was getting scraps from leather workers and had no idea what to look for. I usually just pulled on it to see how stretchy is was. Now, when checking out leather scraps from shops or "raccooned" from other things, I do a "tear test":

    [ame]https://www.youtube.com/watch?v=IohD3f7FgjM[/ame]

    I don't know if it was the type of leather or if it had been sitting on the dashboard of a hot car for a year, or if it was just way too old, dunno. But I ended up with a whole stack of crap pouches. Silly.
     
  2. Flipgun

    Flipgun Well-Known Member

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    You don't have a stack of crap pouches Bro. You have a stack of hanging BB targets.
     
    SteelJunky likes this.

  3. bigdh2000

    bigdh2000 Administrator

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    Leather is like wood. There is a strong direction ("grain" ) and a weak direction. You also have the equivalent of pine and the equivalent of ironwood. As you alluded to, there are also environmental factors that cause additional variations.
     
  4. TheNewSlingshotGuy

    TheNewSlingshotGuy AKA- "The Raccoon"

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    Not sure if raccoon leather is any good........:)
     
  5. Jeb

    Jeb Baba Hunter

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    Hey, now there's thinking! Good idea.

    Yep. This leather tore equally easily in both directions. Bad leather.


    Ha!
     
  6. Bone

    Bone Slingshot Shooters

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    There are so many fake leathers too. That's what it looks like to me.

    Grain on skin......I work leather and the hides have a grain but not like one would think. It's a grain in a way as it acts different from one part of the animal to another. In other words what's going on is, its a live animal where different parts of the hide/skin need to move more or stretch more then other areas. Like the belly.....it stretches more then the back. But......does a section of the same area stretch more in one way then the other? Probably but not in all areas such as the back area. Now where stretching the skin or where it folds or wrinkles as the animal is alive is another story. There is also differences on tanning processes. Leather that sees the outdoors a lot like shoes or saddles is treated in a chrome process making it more durable and hard. Like Dan said many variables here. Hope that helped some.
     
  7. Jeb

    Jeb Baba Hunter

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    Sure does, Bone. Thanks for sharing. So chrome tanning is stronger than vegetable tanning?
     
  8. JimRhodo

    JimRhodo Junior Member

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    If it's any consolation the Painted Horse Christmas decoration has one of your pouches
     
  9. Jeb

    Jeb Baba Hunter

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    Glad it's getting some use, but I definitely owe you a replacement for that sorry excuse for a pouch.
     
  10. JimRhodo

    JimRhodo Junior Member

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    The TBG was excellent in fact now I've seen how looped TBG is attached to the Toucan and Cougar I'll start using it on my Thunder.
     
  11. Bone

    Bone Slingshot Shooters

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    @Jeb......Well......yes. It seems so. When I cut leather that is chrome treated it's tough. Seems harder too. It doesn't take tooling work very well either. Yeah lots of different kinds of leathers and man made stuff too. Here's another tid bit. Leather is like a felt which is a mesh of fibers clinging together. Leather seems like that to me. That's why when we talk grain it's not the actual grain but the way the skin moves which determines the characteristics of the grain/skin. It's actually complicated. I'm still looking for that perfect leather. I want to play with some kangaroo leather soon. I think it's a better choice. Decisions decisions what to play with next. :)
     
  12. seppman

    seppman Folding-Ladder Expert

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    Definitly kangaroo leather, Bone!
    And I just want to throw in here: some guys like Be like ultra light and very small pouches. These are handling "stress" better than bigger ones, even if they are very thin, since they are more "compact". Others like to have some more material between the fingers and like a thicker and heavier pouch. Laminating two really thin kangaroo pouches together combines those two things with the cost of adding some extra weight. On my list of experiments aswell, since Lars (LW) gave me three of his laminated pouches on the last gathering. Leon13 (as a professional bag-maker/tailor) suggested "rocklim" leather glue, but any other textile or wood glue would do aswell. Maybe those thoughts are interesting for anyone aswell. I'll put up a photo of the laminated pouches when I am back home tonight and don't forget.
     
  13. Bone

    Bone Slingshot Shooters

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    Thanks sepp! I noticed that I'm making pouches smaller now as well. Less stretching overall.
     
  14. Crackerbrown

    Crackerbrown New Member

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    This is a great thread!
     
  15. JimRhodo

    JimRhodo Junior Member

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    I've been getting calf skin pouches as they are tough light and looped 1745s don't tear them.
    But they do s-t-r-e-t-c-h.
     

    Attached Files:

    Last edited: Dec 14, 2015
  16. Crackerbrown

    Crackerbrown New Member

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    I brain tan deer hides like the Native Americans did and way too stretchy. Good for clothes and moccasins but not for pouches.
     
  17. seppman

    seppman Folding-Ladder Expert

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    Stretching is not THAT big of a problem, aslong as you don't have a "center" hole and it stretches unsymmetrically. On your picture, using the pouch without center hole, it's no problem. On the other hand... one can always decide to go the other way... and mass-produce pouches... chrrrchrrchrr.
     
  18. Dephnne

    Dephnne New Member

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    If you also do a tensile test of fabric, I would like to recommend a useful instrument which i called elmendorf tear tester.
     
  19. Shadowfox

    Shadowfox Member

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    Though a bit l8 to the table may I add that kangaroo leather is said to be the best pouch leather as it is both very strong and very thin and light too.
     
  20. Blankwalker

    Blankwalker Active Member

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    Mine was coming to thin and a bit weak, because it’s tanned, glueing Doubles at the side solved the problem..

    Looks like the uncolored stuff would be more suitable

    http://s1121.photobucket.com/user/blankwalker/media/DSC_0431.jpg.html