Bodycords are one of the more common points-of-failure within the scoring system, so it is important to know how they work, and more importantly, how to fix them. The previous article illustrated the three wires in the bodycord and what the wires connect to, so if you are not familiar with the connectors, it would be a good idea to go back and review.
The best way to test the lines of a bodycord is with a multimeter, and in my opinion, analog multimeters are better suited for testing than the digital variants, as it's easier to see the needle dance if there are slight breaks in the circuit. Here is an example of an analog multimeter:
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We will use this to test the resistance of the lines; m.29 & m.31 of the USFA Rulebook state that the maximum resistance for any part of the bodycord cannot exceed 1 Ohm, though ideally, there should be no resistance whatsoever (0 Ohms).
To test the lines, set the multimeter to the lowest scale of resistance that is not the continuity tester; on my multimeter the scale is x10, though some use x20 or similar scales. Next, simply attach your leads to the end points of each wire on the bodycord, and if all is good, the needle should move from the left side (infinite resistance) to the far right at zero (no resistance). The picture below shows the 'B' line being tested on a 2-prong German bodycord:
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However, if you connect your leads and the needle stays pointed towards the left, you know there is a break in this line's circuit somewhere. The picture below shows the 'A' line being tested and the multimeter indicating infinite resistance:
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Okay, now we know how to test the lines, let's look at how to fix them. We'll start with the 'A' line on a foil & saber bodycord, partly because the 'B' and 'C' lines all end in a terminal of some sort, whereas the 'A' line ends in a crocodile clip. The most common point-of-failure in the 'A' line is right below the crimp point, for the simple fact that if the wire isn't reinforced, this is where a lot of stress gets put on the wire, eventually causing the metal wire under the insulation to break. The following picture illustrates where the break is in this particular bodycord:
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To fix this, we need to:
- desolder the wire on the clip
- undo the crimp
- cut the wire back
- reinforce the wire
- re-crimp and re-solder the wire to the clip
A pair of third hands are really handy for this job:
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I'm not going to cover wire cutting and soldering in this article, but I will mention that if you don't want to be doing this particular repair frequently, you should get some heat shrink tubing and put it over the wire around the crimp point; this will help alleviate the stress on the wire. Also, for foil & saber, the 'A' line must be soldered to the crocodile clip, and the solder cannot be covered with any insulating material.
Moving on to the wires that end in terminals (or a bayonet), there are usually three reasons why you would be getting any resistance on these lines:
- There is a layer of oxidation on the terminal
- The wire is no longer connected to the terminal
- The wire is broken somewhere between the terminals
The first reason is fairly simple to fix. If the terminals look dull and dark, such as in this picture:
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Then the problem could be as simple as a slight layer of oxidation on the terminals. You can use either an emery file or some fine grit sandpaper to remove the oxidation and your resistance should drop back down close to zero.
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The second reason for a line with high resistance is the wire has become disconnected from the terminal; usually this is a (fairly) simple problem to fix. First we'll look at some 3-prong connectors (reel end) and then we'll explore the most common 2-prong and bayonet connectors.
There are two main covers for 3-prong connectors: hard cover and soft cover. This first picture shows a 3-prong connector with a hard cover; to open it, you must unscrew three screws from the inset nuts on the reverse side.
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The wires in this connector go into the terminal from the side, and a small brass screw on the bottom of the terminal secure the wire in place. These types of connectors are also prone to having the wire break at the point where they enter the hard cover, so it may be a good idea to reinforce that area with some heat shrink tubing.
There are a multitude of different soft covers for 3-prong connectors, the most common ones are illustrated below. The first one is made by Leon Paul:
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The wire on the Leon Paul 3-prong connector is inserted through a hole at the base of the terminal, and a small steel screw with a point is screwed in from the bottom of the terminal which compromises the wire's insulation, creating the contact for the electrical circuit, and also securing the wire in place. This type of connection is different from the others in that the insulation is not stripped from the wire to make contact with the terminal.
One last word about Leon Paul connectors in general, is that usually the reason for elevated levels of resistance has to do with oxidation of the wire and/or screw, a symptom some refer to as Leonpaulitis, and a good quick fix is to back the screw off a few turns, and then re-tighten to break off some of the oxidation and bring the resistance back down to zero.
The second common soft cover 3-prong connector comes from Prieur, and belongs to a French-style bodycord:
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For the Prieur connector, the wire is inserted at the bottom of the terminal, to which the terminal and wire are inserted into the connector, and a small brass screw secures the wire to the terminal, and the terminal to the connector.
The last soft cover connector we'll be looking at is used by Negrini in some of their bodycords:
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In this design, the wire is soldered to a contact washer, which is secured between the terminal and the connector base when the terminal is inserted through the base and secured by a nut at the bottom.
Moving on to the 2-prong and bayonet connectors, we have a much more varied selection. First we'll examine the typical 2-prong German connector:
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The hard cover housing can be disassembled by removing the two flat-head screws that hold the housing together, and the small Philip's-head screw that holds the retaining mechanism together. The terminals used in the picture above are the same type as the hard cover 3-prong connector we looked at previously.
Next, from Leon Paul we have the French-style 2-prong connector and the Leon Paul bayonet:
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The wire connects to the terminals in these two connectors the same way as their 3-prong connector: the wire is inserted into the hole in the terminal, and a pointed steel screw at the bottom of the terminal breeches the wire's insulation, both making the contact for the electrical circuit, and also securing the wire in place.
Another fairly common 2-prong French connector comes from Prieur:
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This design has the wires coming up from the bottom through the top, where the wires separate and come down through the connector again, finally coming out the bottom and into the terminals which are housed in the connector; again the wire is secured to the terminal, and the terminal held in place in the connector, by a small brass screw. A common point of failure in this design is at the bottom of the connector where the wire attaches to the terminal.
Finally, we have the Italian bayonet from Negrini:
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The wires are held in place by a "wire stop", which helps to prevent the wires being pulled off the terminals accidentally. Again, Negrini solders the wires to the terminals, making the connection even more secure. Replacement, or re-soldering of the wires simply requires the removal of two small Philip's-head screws on the "wire stop" to free the wires, and then soldering the wires to the inner and outter terminals ('B' line is the inner terminal).
Last but not least, the third common fault in a body cord is a break in the wire. Some bodycords use a transparent insulation, making locating the breaks easier, but most are opaque, and require some investigating. The first thing you should do is check for obvious signs of damage to the wire, such as a sharp bend, crease, or discoloration in the insulation. If you see such an area, this is a good place to begin testing, but if not, then it is best to start testing right behind the connectors. The easiest method I've found is to take a small sewing needle and use it to penetrate the insulating layer of the wire, and attach one of your multimeter leads to one of the terminals, and the other to the needle; if your multimeter still shows infinite resistance, try the opposite terminal on the bodycord and test again. Repeat these steps until you determine where the break is, and there may be a chance that you can salvage the bodycord, provided, in foil & saber, the 'A' line is separated by at least 40cm from the crocodile clip to the 3-prong end.