Brittle wires?

[melensdad]

Had to replace an Epee blade yesterday at a tournament for one of the students. Ran into what I can only describe as a brittle wire.

Every time I tried to tighten down the wire on the screw to hold it in place the wire broke. I tried it under the washer. I tried it over the washer. I think it was the 5th or 6th try before it held in place and that time I didn't tighten it very hard. The other wire was NOT a problem.

Tested the weapon on my check box and it was showing a fault. I've got a new Leon Paul test box and am not used to all the lights yet so I tested it again on a Favero test box and it tested fine.

The student took the weapon into competition and it started faulting.

I tested it again and it was showing faults. Took the whole weapon apart again and the wire I was having problems with was broken under the insulating felt.

So I'm curious, how often do you run into wiring problems like this? Is it a fluke that only 1 wire was brittle?

[Purple Fencer]

Considering the size of the wires (or lack thereof), I'm amazed I don't run into more brittle wires....the most common prob I run into re epee are Sport 7 ones popping out of the crimp when I pull them tight.

How are you stripping the wires? That might be a contributing factor.

[melensdad]

How are you stripping the wires? That might be a contributing factor.

I was using a razor knife to gently scrape the cloth insulation until it began to fray then I unwound the insulator. First time the wire broke I chalked it up to cutting the wire with a bit too much pressure from the knife. Second time I had doubts it was the knife. Third time I didn't even use the knife but simply unwound it with my fingers and pulled it back.

And while the knife MIGHT be guilty of cutting into the wire when I stripped the insulation off the end so it could be screwed down, what would explain the wire breaking off about 1.25 inches INSIDE the bell? (and no, I did not crush it under the grip)

FWIW, I've tried wire strippers with mixed results in the past.

[K O'N]

Had to replace an Epee blade yesterday at a tournament for one of the students. Ran into what I can only describe as a brittle wire.

Every time I tried to tighten down the wire on the screw to hold it in place the wire broke. I tried it under the washer. I tried it over the washer. I think it was the 5th or 6th try before it held in place and that time I didn't tighten it very hard. The other wire was NOT a problem.

The wires grab on the threads. They're supposed to go under the washer, and that's supposed to keep the grabbing from happening. You can use these:

http://sword-masters.com/catalog/pro...oducts_id=1332

or you can make your own, out of solid small gauge copper wire. Make a loop around something round and a scooch bigger than the post, twist a pigtail, use like the terminal shown above.

Tested the weapon on my check box and it was showing a fault. I've got a new Leon Paul test box and am not used to all the lights yet so I tested it again on a Favero test box and it tested fine.

Just get a meter. Those test boxes drive me crazy.

The student took the weapon into competition and it started faulting.

What does that mean? It was dead?

I tested it again and it was showing faults.

Grounding? Dead?

Took the whole weapon apart again and the wire I was having problems with was broken under the insulating felt.

So dead, then.

So I'm curious, how often do you run into wiring problems like this? Is it a fluke that only 1 wire was brittle?

I'm pretty sure all the wires in a batch come off the same big spool, so it's hard to imagine that one would be different than the other. Not impossible, but way down the list of likely.

I would say, A) you pulled hard on it when you were cranking down on the post, and broke it, or B) it got nicked somehow, or C) it got bent sharply and was weak even when straightened out, or D) it got a loop in it which you failed to see and pulled down to a tiny crimp which then broke.

I was using a razor knife to gently scrape the cloth insulation until it began to fray then I unwound the insulator. First time the wire broke I chalked it up to cutting the wire with a bit too much pressure from the knife. Second time I had doubts it was the knife. Third time I didn't even use the knife but simply unwound it with my fingers and pulled it back.

And while the knife MIGHT be guilty of cutting into the wire when I stripped the insulation off the end so it could be screwed down, what would explain the wire breaking off about 1.25 inches INSIDE the bell? (and no, I did not crush it under the grip)

Relax, we believe you. Some people use a lighter to burn off the insulation, which might or might not make the wire a bit brittle there.

FWIW, I've tried wire strippers with mixed results in the past.

A razor blade or exacto knife is the standard, I think.

K O'N

[Purple Fencer]

I strip with sandpaper first. if it's a French wire, there's no additional insulation to remove. if it's a German, I burn off the inside insulation (the trick is to both remove the outer wrap first to cut down on the heat buildup, and not to lay the flame on the wire for an extended period...one pass at a moderate speed should do it....you can usually see either the interior insulation burning off, or the secondary flame from the same)...then run sandoaoer over it a fe times to get off any residue.

Note....if it's a french foil wire that's blue, it DOES have that 2nd insulator (Sport 7)

One other question for the OP....how many times are you wrapping the wire around the socket post???

[melensdad]

The wires grab on the threads. They're supposed to go under the washer...

Yup but it broke that way too. Twice. This was the first time I've had this problem. Granted I've only been doing this for 1 high school season with some training at the club over the prior year so my experience is limited to installing maybe a couple dozen blades, reconnecting loose wires sockets to double that number. I am mechanically inclined, build rifles and have restored vehicles. But this just baffled me with all the breaks on this one wire. The other wire on this blade didn't cause me any problems.

One other question for the OP....how many times are you wrapping the wire around the socket post???

One wrap.

[Purple Fencer]

One wrap.

Ah....I thought you might be wrapping multiple times....that tends to have the wire cut itself.

I've had the same problem on epee sockets...rarely on German foil ones (but frequently on &^#^$ french ones!).

The solution is simply not to crank the socket so tight. Once I started only getting it snug, I stopped having so many breaks.

[melensdad]

The solution is simply not to crank the socket so tight. Once I started only getting it snug, I stopped having so many breaks.

Well to that I concur, but I'm still baffled I had the problem multiple times on 1 wire.

[DHCJr]

First, one thing that no one mentioned is to place the spaghetti under the washer. This acts as a strain relief.

What is been said above, the wire should only go about ¾ of the way around.

Also what you want to do abrade the insulation off the wire. If you use a knife or Xacto you have the blade angled away from the direction you are scraping. / -->

Just getting off the cloth may not have gotten the insulation off. There is usually a second insulation. With French style it is a second cloth layer, but with most it is varnish or similar. Look at the color of the wire. With the varnish it will look dull and brown. Once the varnish is off it will have a bright golden color.

Most Armorers will tell you burning off the insulation is very bad.

On why one test box would show good and one not. Many boxes use LED which allow K ohms and still show good. The machines and better test boxes will show it as bad.

[melensdad]

First, one thing that no one mentioned is to place the spaghetti under the washer. This acts as a strain relief.

What is been said above, the wire should only go about ¾ of the way around.

Yup, I know it goes under the washer. Broke it that way, TWICE.

And I only wrap it once by making a "U" shape in the wire. Broke it that way under the washer and over the washer.

Honestly if I thought I had screwed up then I would not have started this thread. I really don't think I screwed up. The more I considered what happened the more I wondered if it was simply a bad wire. Like I said, on this blade all the problems were with only 1 of the wires. That single wire broke at least 5 times.

[SJCFU#2]

Assuming there's more than a small stub of a wire left you could try splicing a short piece of new wire (such as the extra wire left over after a rewiring) onto the end of the old one and cover the splice with the spaghetti insulation. That way you may be able to get a decent piece of wire to wrap around the socket and the hopefully the spaghetti will keep the old wire from breaking in the middle.

And if there isn't much of a stub left or if the wire does break inside the spaghetti then perhaps it's time to cut your losses and rewire the entire blade. I'm inclined to agree - it sounds like you may have gotten a bad wire. Hopefully it was just one and you didn't get a bad batch (did I miss it or have you yet to mention who's wire it was?).

[twisterfencing]

Sounds like a factory wired Stm blade with a Stm wire. These things are so thin and brittle, they will break at a resting posistion.

If you have run out of wire to grab now, time to either solder on a new pc of wire (graft), or rewire the blade.

Hate it when this happens,

Gary Spruill

[brtech]

I'm now going to explain how you add a bit of wire when it's too short (graft). We all do this if we need to get the weapon back on the strip, but it's also not a permanent fix: rewire when you get a chance.

The first thing to do is have some large diameter spaghetti. Some spaghetti just isn't wide enough to take a splice. There is some really huge stuff that I have for really tough cases, but I keep a hank of some medium large diameter that Twister gave me a while back which I reserve for this procedure.

If you can, the best way to splice is to twist the remaining end and a new piece of wire to make a good mechanical joint, then solder it. Most of the time, that makes a the joint too big to get the spaghetti over. The twist is in line with the wire, not a pigtail. Cross the wires in an X, then twist the remaining end around the other side. You need to get the ends to lie flat: a needle nose pliers can help. Solder carefully, with a minimum of solder. You might have to cut off a bit of the solder (NOT the wire) at the end. Use the needle nose again to get as small a diameter as possible, and see if you can get the spaghetti to go over it.

I usually end up with an inline lap joint. When properly done, it is strong enough. You strip 3/8" from each end. Get the stripped ends VERY shiny. I use emory cloth or sandpaper. Then tin the ends with solder individually: heat the wire, add a very small amount of solder to just coat the stripped end. Tin both ends.

Then align the stripped ends so they overlap in-line with each other, melt a tiny dab of solder on the tip of the iron and apply your soldering iron to the joint. You usually don't need any more solder. Just get what's on the ends and the tip to flow into each other. For extra special help, dip the tinned wires in flux before soldering, but don't have any excess: just a thin coating. You are left with a joint that is 3/8" long, and only slightly wider than two wire thicknesses. It's surprisingly strong.

How you hold the wires to get that joint is tough. I actually do it without a helper. I hold one wire with my middle and index finger, and the other wire with my thumb and ring finger on the same hand, and hold my soldering iron with the other hand. While I can't move the joint holding it that way, I can hold it in place well enough to allow me to get the solder to melt.

[twisterfencing]

brtech:

Thanks for covering my buttocks!

I forget sometimes who I am writting too and that person's experience level.

Gary Spruill

I'm now going to explain how you add a bit of wire when it's too short (graft). We all do this if we need to get the weapon back on the strip, but it's also not a permanent fix: rewire when you get a chance.

The first thing to do is have some large diameter spaghetti. Some spaghetti just isn't wide enough to take a splice. There is some really huge stuff that I have for really tough cases, but I keep a hank of some medium large diameter that Twister gave me a while back which I reserve for this procedure.

If you can, the best way to splice is to twist the remaining end and a new piece of wire to make a good mechanical joint, then solder it. Most of the time, that makes a the joint too big to get the spaghetti over. The twist is in line with the wire, not a pigtail. Cross the wires in an X, then twist the remaining end around the other side. You need to get the ends to lie flat: a needle nose pliers can help. Solder carefully, with a minimum of solder. You might have to cut off a bit of the solder (NOT the wire) at the end. Use the needle nose again to get as small a diameter as possible, and see if you can get the spaghetti to go over it.

I usually end up with an inline lap joint. When properly done, it is strong enough. You strip 3/8" from each end. Get the stripped ends VERY shiny. I use emory cloth or sandpaper. Then tin the ends with solder individually: heat the wire, add a very small amount of solder to just coat the stripped end. Tin both ends.

Then align the stripped ends so they overlap in-line with each other, melt a tiny dab of solder on the tip of the iron and apply your soldering iron to the joint. You usually don't need any more solder. Just get what's on the ends and the tip to flow into each other. For extra special help, dip the tinned wires in flux before soldering, but don't have any excess: just a thin coating. You are left with a joint that is 3/8" long, and only slightly wider than two wire thicknesses. It's surprisingly strong.

How you hold the wires to get that joint is tough. I actually do it without a helper. I hold one wire with my middle and index finger, and the other wire with my thumb and ring finger on the same hand, and hold my soldering iron with the other hand. While I can't move the joint holding it that way, I can hold it in place well enough to allow me to get the solder to melt.