LP Body Cord Partial Failure

Discussion in 'Armory - Q&A' started by sdubinsky, Jan 11, 2018.

  1. sdubinsky

    sdubinsky Made the Cut

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    I have a six year old LP body cord that is occasionally failing. On some strips it works, on some it doesn't. I've already tried taking the casing off both ends and twisting the screws back and forth a couple times. It works reliably on my test box, but not always on strip. What can I do to decrease the resistance further?
     
  2. Purple Fencer

    Purple Fencer Podium

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    You might replace the entire cable if it’s corroded.

    Could also be corrosion on the screws that
    Make contact with the socket...or loose screws there.

    It’s not always the wire.

    Sounds like a new vid I need to shoot!
     
  3. Inquartata

    Inquartata Podium

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    Wait, people keep telling me that bayonet cords never break or fail. How can this be?
     
  4. neevel

    neevel Armorer

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    Have you checked along the entire length of the wire for breaks? It could be that there is a break somewhere in the middle of the wire that won't be turned up if you're flexing the wire right below the plugs on your test box. Hold the wire up to a light and closely look for any possible breaks by moving down the wire and trying to stretch each section- you will be able to see the wire separating inside the clear insulation. Spots of green or black discoloration inside the insulation can also indicate spots where there may be a break. You can order new wire for the cord from Leon Paul

    Also, what do you mean by test-box: a simple LED box, or something with an Ohmmeter? LED testers will often still light when the resistance is high enough to start affecting scoring boxes.

    One more thing: are the plastic brackets on the 3-pin end(s) intact? If those are broken they won't keep the pins in secure contact with the socket terminals, which will result in intermittent failures. Replacement 3-pin ends are sold by LP.
     
  5. EspadaMK

    EspadaMK Made the Cut

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    Maybe you just look gullible. They break far more than the German two pins.
     
  6. EldRick

    EldRick Podium

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    You could cut the wires back 3/4" shorter, and re-insert. It's sometimes oxidation near the ends on that part of the wire most exposed to air.
     
  7. dcchew

    dcchew Podium

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    You got 6 years worth of use of a body cord and you're complaining? Pretty much every piece of fencing equipment will require periodic maintenance of some sort.
     
  8. Zebra

    Zebra DE Bracket

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    Especially body cords.
     
  9. sdubinsky

    sdubinsky Made the Cut

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    I don't think this is the case, because it works reliably on some strips and with my test box and not at all on others. It's a simple LED box. The plastic brackets are intact.

    Nope, not complaining, looking for advice on what maintenance to do.

    Because it's epee :p

    I think I'll try this. Thanks!
     
  10. neevel

    neevel Armorer

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    Use an ohmmeter to get actual resistance values for the lines. Different scoring boxes will start 'noticing' high line resistance at different points, and the condition of the reels and cables on a strip can affect the total resistance seen by the box.
     
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  11. K O'N

    K O'N Podium

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    Yes, certainly put a meter on it, first thing. A light on/light off test box tells you far less than a meter's needle.

    Next, if you've already done the loosen/tighten cycle on all the screws and that didn't work, take all the screws all the way out and clean the points. Trim an inch or two off each end of the wire and rebuild. If it still shows high resistance the wire is shot. Honestly, six years is pretty good to get out of a heavily used body cord. But IME the wire goes bad from the ends, so trimming off a bit may save you here.
     
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  12. Mac A. Bee

    Mac A. Bee Podium

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    Also, try pulling the exposed wire end. If it separates, you'll know how much to cut back both leads.
     
  13. brtech

    brtech Podium

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    Bayonets fail MUCH less often in my experience, but they get the high resistance problem. So, a small amount of maintenance gets you a very reliable and long lasting cord. It's hard to find 30 year old 2 pin cords. We see them, but we see a lot more 30 year old LP bayonet cords. It's very unusual for LP wire to be "shot" in 6 years. A break near a flex point, uncommon, but possible, but that would be repairable. Usually, the only way you get a failure in the middle of an LP wire is some kind of insulation break which only comes about by some kind of serious mistreatment. Follow Neevel's advice. It's what I would do.
     
  14. Zebra

    Zebra DE Bracket

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    I don't recall which company makes them, but somebody's epee cords are made from a very soft and flexible-feeling wire (compared to the stiff wire in the Absolute cords), and those cords are prone to (frustrating!) breaks in the middle of the wire as Neevel points out.
     
  15. neevel

    neevel Armorer

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    Are those the ones from The Fencing Post? They're using wire from Cicoil, who produce high-flex motion control cables- I believe Saul had the wire he uses for them custom made. As an experiment, I found some similar high-flex motion control wire (with clear insulation, however) from McMaster-Carr and bought a length of it to make up a body-cord. What I discovered is that while the wire was very supple and flexible, its tensile strength was not up to the task and would develop breaks down the length of the cord as you describe. LP wire by contrast has a good combination of flexibility and strength in my experience, but that's no guarantee that something won't go 'just-wrong' and cause a break further down the wire. The strongest wire for body cord applications that's readily available is the Negrini wire (though it won't be as supple as LP's wire).
     
  16. Zebra

    Zebra DE Bracket

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    I don't think so--they had clear insulation with a black identification stripe.
    And I think you're right on the button when you say the issue is one of tensile strength. Making the insulation flexible takes away from its strength.
    What I did when one of those wires failed was to strip it and cut it down an inch or two at a time until the conductivity was reliable again. Most of the breaks were within a few inches of then end.
     
  17. neevel

    neevel Armorer

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    The insulation actually isn't going to contribute much to tensile strength. It's a combination of the metal used for the wire, how fine and how many strands there are in the wire, and whether there's any reinforcement (such as the steel core that the Negrini wire uses).
     
  18. Purple Fencer

    Purple Fencer Podium

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    Like people securing the cord by clipping the A line clip around or even *shudder* on top of the cable.

    I die a little inside every time I see that one.
     
  19. Mac A. Bee

    Mac A. Bee Podium

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    When failing a cord on-strip, I clip to the failing end's plug, informing the armourer which end to begin trouble-shooting.
     
  20. Purple Fencer

    Purple Fencer Podium

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    Kinda hard to do that with an epee cord.

    The usual indicator I see is tying a loose knot at the end where the problem is.
     

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