Welding case hardened steel

  1. mike os

    mike os just a little insane.....

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    North Wales
    Unfortunately battrey powered grinders changed the rules..., even proper locks etc are vunerable now,,

    Only locks that last more than a minute are Chubb hercules locks but that's really only because of the amount of metal in them
     
    Hopefuldave likes this.
  2. Hopefuldave Intergalactic pot-mender

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    1,709
    Location:
    The Shed of Danger, surrey, England
    Which is why container yards put fairly hefty steel boxes around the locks that prevent angle grinders getting to the lock...
    [​IMG]
    Dave H. (the oher one)
     
  3. mike os

    mike os just a little insane.....

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    Theu take another couple of minutes and disks ....
     
    Last edited: Aug 15, 2020
  4. TechnicAl

    TechnicAl Member

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    Rotherham
    I dont think theres a matching consumable available, so youve got a choice to make. You could use mild steel to weld it and then cap off with a hardfacing wire.........or you could try 1CrMo or 2CrMo.......but it might crack......It depends on the thickness / stiffness and what the application is....I dont know any of that.

    PS I am assuming you are joining it through thickness........a weld on the surface would be a different consideration
     
  5. brightspark

    brightspark Member

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    yarm stockton on tees
    so they just cut the hinges off and pull the door open from the side :vsad:
     
    metalmelt likes this.
  6. wyn

    wyn Member

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    3,129
    Location:
    Cardiff
    A lot of containers now have "tabs" welded to the inside hinge part of the door.
    If the hinges are cut it won't pull open.
     
  7. pedrobedro

    pedrobedro Man at Matalan

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    CX Derbyshire
    They don't want to spend any time getting in. Anything that slows the job down is a good thing. A box over the locks and frame pins so they will not pull out from the hinge side are going to make thieves think twice.
     
  8. 8ob

    8ob Forum Supporter

    Messages:
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    Location:
    moscow on thames
    I have seen a few clever ideas for securing shipping container doors. One was a double skin lock box that was filled with ball bearings, not big enough for an angle grinder to get at the lock and tough enough with the double skin and bearings to destroy a thin disc. Another was just 30mm solid bars pushed through the side of the container, there were tubes on the inside of the door for them to slide into, despite several unsuccessful attempts by the great unwashed to get in no one ever bothered to look at the side of the container for the bars.

    Bob
     
    mechman, Brad93 and Maker like this.
  9. Brad93

    Brad93 M J B Engineering

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    Location:
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    Mild steel box section won’t really lend itself to case gardening unless you add a tonne of carbon to the mix
     
  10. Brad93

    Brad93 M J B Engineering

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    Essex
    Love that idea
     
  11. metalmelt Member

    Messages:
    381
    Location:
    UK
    If you are that intent on security then make a laminate using different materials inside your box section, it needs different types of materials of diffferent hardnesses along with something light and flexible to snag the cutting disc, they make various types of laminates for security purposes and often this is carbon fibre strings or braid dropped onto the outside of the box section and held at the top with superglue, this is then filled with reject ball bearings and filled with liquid fire cement to fill the voids, they then weld the top on.

    Liquid fire cement of the correct grade contains diamond particles and these, along with the reject bearings rip the disc to shreds and the carbon fibre strands snag the blade and either stop the angle grinder or pull it out of their hands; case hardening is only thin and easily cut through.
     
  12. Seadog

    Seadog Forum Supporter

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    Location:
    NE London - UK

    A small clay club that I go to adopted this method after having the traps stolen on a couple of occasions.
     
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