A Folding Long Sword?

Discussion in 'Knives, Swords, and other bladed weapons' started by Odins_Zornn, Aug 6, 2013.

  1. Tremoside

    Tremoside SINdustrial designer

    566
    5
    18
    Hi Odins,

    Thanks for the invitation.
    Have to say, you have great help here with Tysonpapa and Will. And I do agree with Will about a simplified proto made of aluminum cutted with plasma, or even multiplex by hand/jigsaw.

    I don't know the exact dimensions, but this hinge joint looks like a bit narrow for me (thickness). If you calculate with forces not normal to the edge it could be dangerous. The smallest force coming from sideways can add a huge force to this thinner side. The darker grey closing plate on the mid part is really under pressure.

    You also have to calculate with the stopping forces and surfaces during opening (or release if it's assisted). Aaand locking. The lock itself might be harder to design than the hinge.

    As a 3D printed metal part it's not really working. It is possible to print I think now, but never tested sketchup models for print. I experienced ovality problems with printed metals. There is a heating process after the print and that's hardly controllable without heat analysis of the model. Plus you have to think of printed metals as "impossible casts". Details are like casts details, but you can make underturns/undercuts.

    Tested some printmetals for stress. Those are strong, but brittle at the critical force. Aluminum (and of course steel) is more flexible and reliable under dynamic stress. Suggest you to stick with it. Titan is hell to work with. Carbon eats up time, tool and money.

    If I were you I might start with a paper model for real life proportions, then plywood test with alu joints. For a final version an alu blade core and thin layer of ssteel cutting edge are a quite balanced combo. Light enough to open fast, but still heavy enough to make an impact on something.

    For an edge you can buy some (for eg. Tramontina) knives cut them up and insert between two layers of aluminum scales. You can even made a sword with serrated edge :D

    It's a fine project! Go for it! It needs lotsa real life tests before you can make actual decisions on joints, locks, hinges and stopping shapes.

    Keep it up mate! And stay :cool: :D

    Tremo
     
  2. Odins_Zornn

    Odins_Zornn Noob

    196
    0
    0
    For MaddyMax and everyone else who wanted to see how the blade folded.
     

    Attached Files:


  3. Odins_Zornn

    Odins_Zornn Noob

    196
    0
    0
    And again, halfway open.
     

    Attached Files:

  4. Will

    Will Thread Hijacker

    3,375
    2
    0
    Here is another example on the shaft of my line-trimmer. First you can see it in the locked position, then I pushed it down so you can see the way it will disengage to allow movement
     

    Attached Files:

  5. Tremoside

    Tremoside SINdustrial designer

    566
    5
    18
    Ups, I just repeated a wise man! Excuse me, missed your post MaddyMax :eek:
     
  6. MaddyMax

    MaddyMax New Member

    1,015
    0
    0
    telescopic crutch. :D
     
  7. MaddyMax

    MaddyMax New Member

    1,015
    0
    0
    i will never be as exact as you in describing things!
     
  8. Will

    Will Thread Hijacker

    3,375
    2
    0
    Thanks Tremo, you are absolutely correct about a model made from wood first! That would be the easiest way to test by far!
     
  9. Will

    Will Thread Hijacker

    3,375
    2
    0
    Exactly, exactly!! Thank you, I was going crazy trying to explain that!:confused:
     
  10. Odins_Zornn

    Odins_Zornn Noob

    196
    0
    0
    Your words and the clip confused me, but what is on the pole, i know. Besides the hinge mechanism and the handle, where do you think I need that?

    To Tremoside: thank you for the printing advice, your material rundown, and your blade advice. I will make a multiplex model because you suggested it. The locking mechanism has already been worked out in my head, its a little more elegant and streamlined than the telescopic crutch that Will showed us. The hinge's lateral stability is concerning, even with the ideas i have to help with stability.
     
  11. Will

    Will Thread Hijacker

    3,375
    2
    0
    Sorry for the confusion. I'm not sure if you need it any particular spot on your design, I was just throwing ideas around more than anything. And they are rather crude compared to what you will design, I'm sure.
     
  12. Odins_Zornn

    Odins_Zornn Noob

    196
    0
    0
    Crude isnt a word i would use to describe that, effective comes to mind though. The only reason those wont work, is that the release has to be flush with the blade.
     
  13. Odins_Zornn

    Odins_Zornn Noob

    196
    0
    0
    So I've added two of th things you suggested: the hinge support and the hinge lock.
     

    Attached Files:

  14. Barkundra

    Barkundra New Member

    42
    0
    0
    I love this idea and even though I don't know much about swords I think this could work.