In the sport of modern, Olympic-style fencing, scoring is done electrically. For the electrical signal to travel from your weapon to the scoring machine, the signal needs to travel:

through a wire in your weapon (except sabre)
up your sleeve and down your back through your bodycord
through a long cable that connects you to the reel
across the floor in a floor cable
into the scoring machine

This Instructable describes how to test and repair a bodycord used when fencing epee.

Tools Needed: screwdriver, small screwdriver (5/64), pliers, wire cutters, wire stripper (or a knife), something to test resistance (e.g., volt-ohm meter, continuity tester, or specialized fencing tester such as the Leon Paul TT10)

Step 1: Initial Testing

Before we begin, look at your bodycord. We're going to call the pin that is separate from the other two, the Outside Pin. The one next to it will then be called the Middle Pin. That makes the pin on the opposite side the Inside Pin.

The wires in the bodycord all go straight through. When we take measurements we will be testing the Outside Pin on one end of the cord with the Outside Pin on the other end of the cord. Similarly, we'll test the two Middle's and the two Insides. When we test them, we want to make sure we have low resistance, or at a minimum continuity.

For example, when I tested the bodycord below I got:

Outside-Outside = 0L (no connectivity)
Middle-Middle = 0L (no connectivity)
Inside-Inside = 0.4 Ohms (connected. OK)

From that information, it's no surprise this cord didn't work on the fencing strip. Two of the three pins are not able to transmit any signal back to the machine.

Step 2: Guessing Where the Problem Is

Once you know you have a faulty bodycord, the next difficulty is deciding where the problem is. To try and narrow down the problem, I like to try and guess which end of the wire has the problem using what I call, "The Wiggle Test."

For the Wiggle Test, find a pair of pins that are currently not working. In the example from Step 1, the Outside pins were not making contact, so let's attach our leads to the Outside pins. Now, pickup one end of the body cord and bend the wire just past the end of the plug housing. If you suddenly get connectivity, you've found the end that has the problem.

Step 3: Open the Plug Housing

Now that we think we know where the problem is, it's time to open the plug housing. Using a screwdriver, remove the three screws to reveal the three wires and their pins.

Step 4: Check the Pins

Now that you can examine the pins and wires directly, you should make sure that each wire is securely fastened to its respective pin. Sometimes, the wires will break at the pin and this will cause an intermittent connection.

If any of the wires seem to be loose from their pins, you can tighten them or reconnect them using the small screwdriver. Congratulations, you're done!

If all the pins and wires look good as in this case, you most likely have a broken wire. Slide the sheathing down the wire so you can take a look at the wires.

Step 5: Guess Where the Wire Is Broken

Now that you can see the wires, see if you can see where it might be broken. One place to look is where the wires get crimped at the end of the plug housing.

While the bodycord in these pictures are black, some are clear. If the wire is clear, it makes examining the wire much easier. You want to look for black spots that look as if someone burned the wire. In those black sections the wire isn't burnt, but the wire looks black because it has been stressed and broken in that area.

Step 6: Cut the Wire

Pick a spot on the wire past the crimped section where you think you would like to cut and cut your wire. You will need to strip the wire as well using either a knife or a wire stripper.

Step 7: Retest the Wire

Now that you've cut the wire, it's a good time to make sure that your problem is solved. Retest all three pairs of wires just as we did in Step 1 to make sure you've cut the wire at a good place. Do the Wiggle Test from Step 2 to make sure everything's in good working order.

Step 8: Put the Pins Back On

When you cut the wires in Step 6, the pins were still connected to the old, broken piece of wire. Using the small screwdriver, loosen the screws on the pins and remove the pins from the wires.

Now, thread the pins onto the newly stripped pieces of wire by turning the pin clockwise as you slide it on to the wire. Tighten the screws to secure the wire. It helps to hold the pin with pliers when you do this.

NOTE: When the wires and pins lay flat in the plug housing, the wires prefer to enter each pin in a specific direction. You may notice that when you lay your wires down that you might have to reattach some of the wires.

Step 9: Close the Plug Housing

Lay the pins and wires into the plug housing. There are indentations in the housing to hold the pins, so make sure the pins are resting in them.

Be sure to pull the sheathing back up and over the wires. The sheathing prevents the wires from getting crushed too much by the housing.

Replace the other side of the housing. Tighten with the three 3 screws that we removed at the beginning and your bodycord should be good as new (albeit an inch or two shorter)!