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Swaging dies for cable ends

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  • Swaging dies for cable ends

    Does any one know what pressure is needed to swage ends on 3mm cable? Or how much compression is needed for the crimp?

  • #2
    I think it's going to depend on the manufacturer of the crimp fitting. It's usually recommended that you follow their instructions and use their crimp dies and tool. I would start looking here.

    http://www.nicopress.com/products/

    JL...............

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    • #3
      The handheld cable-end crimper I use for 1/8th (for wire railings) is 16 ton. Wouldn't want much less. This turns a round stainless ferrule into a hexagonal crip. Definitely use the recommended dies matching the ferrule.

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      • #4
        The real test is the pull-out test, where it fails.

        With consistent cable, consistent ferrules, and consistent crimp height after crimping, you can pretty well guarantee the pull-out tension. The manufacturer will have that for their tool and ferrules.

        For some ferrule off the internet, and a tool from somewhere else, who knows?
        1601

        Keep eye on ball.
        Hashim Khan

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        • #5
          I was going to make my own dies and ferrules. The online instructions don't seem to give the amount of compression on the ferrules.

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          • #6
            I just crimped on some #4 welding cables and I noticed this: there are several hundred strands in the cable. This allowes it to bend easily. When it bends the strands slide a little to allow the bend to form. If the end of the cable is crimped tight enough to not allow any strands to move then its crimped just tight enough. This mackes the cable impossible to flex for an inch or two after the crimp. Try to achieve that at a minumum.

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            • #7
              When I was hang gliding a lot, we always did our own cables. Used one of those
              nico presses that looks like a brake pipe flaring tool. Just use the right size nico in
              the right hole and tighten the bolt. Good to go.

              You can imagine how important we thought the wires were on our gliders. Never even
              heard of a problem.

              Wouldn't want to have to do a BUNCH of em with that tool .. but .. a half dozen or
              so wasn't too bad.
              John Titor, when are you.

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              • #8
                Originally posted by ahidley View Post
                I just crimped on some #4 welding cables and I noticed this: there are several hundred strands in the cable. This allowes it to bend easily. When it bends the strands slide a little to allow the bend to form. If the end of the cable is crimped tight enough to not allow any strands to move then its crimped just tight enough. This mackes the cable impossible to flex for an inch or two after the crimp. Try to achieve that at a minumum.
                The OP isn't talking about electrical cables, but I know exactly what you mean with the fine stranded welding cable. With wire rope you will notice that stiffness close to the crimp fitting but it's not as pronounced as it is with the electrical cable.

                JL................

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                • #9
                  Cable swage go/no go gauge-

                  http://www.aircraftspruce.com/catalo...ges/gonogo.php
                  I just need one more tool,just one!

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                  • #10
                    Thanks wierdscience. I think I have found what I need. It looks like for 1/8" cable you want and .250 ferrule and about .032" of crimp or a compression of .218"

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                    • #11
                      The companies that make these have done the research and testing, destructive testing, to ensure that their combination of ferrules and dies will work properly. They have probably spent thousands, tens of thousands, perhaps hundreds of thousands of dollars in this process. They know that with the alloys they use and other manufacturing steps for making their ferrules, their dies will make a reliable crimp with a certain strength that they can guarantee. They probably have a continuing test program to ensure reliability. And you expect them to just give away that knowledge with the instructions? That would not be a good business model. And if they omitted or misstated just one small detail, they would probably be liable for any damages caused by ferrules and dies made by others. Oh, and they will have millions of dollars in liability insurance.

                      A proper crimp on wire, weather mechanical of electrical, is a delicate balance. If there is too little pressure applied, then the wire will just pull out. But crimping causes metal to FLOW and both the ferrule AND the wire will experience this. So, too much deformation can cause the wire to be weakened at the point of the crimp and it can break in half there. I have seen both modes of failure. You have to get it at that proper, in-between point for the maximum strength and reliability.

                      If you want to get into that, ante up. For me, I will just buy the ferrules and dies when I need them.

                      And YES, I have seen the results of some efforts to use incorrect or makeshift crimping tools. They swore that the crimps were OK. Upon inspection I found that quality was all over the place: some OK and others were horrible. Some of them actually just fell apart from handling.

                      You can get cable fasteners that are tightened by hand. I would suggest them and using the proper torque when assembling them.

                      One more thing, most dies are made to work properly if they are FULLY CLOSED. The pressure used is not measured, it is just enough to ensure that the die was fully closed. The die is carefully made to ensure that the proper degree of deformation has occurred when this happens. The die will function over a wide range of actual pressures from somewhat less than the recommended value to quite a bit more.



                      Originally posted by quadrod View Post
                      I was going to make my own dies and ferrules. The online instructions don't seem to give the amount of compression on the ferrules.
                      Last edited by Paul Alciatore; 04-17-2016, 11:13 AM.
                      Paul A.
                      SE Texas

                      Make it fit.
                      You can't win and there IS a penalty for trying!

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                      • #12
                        +1 on that

                        You don't seem to have mentioned what you need to crimp cables for... Maybe its something totally non-critical.

                        As mentioned by Paul A, and above by me, the crimp amount is totally irrelevant.................................... irrelevant UNLESS you know that with THAT SPECIFIC CONTROLLED SIZE of sleeve, to the thou, AND a specific cable, AND a crimp shape and final height, that the result is a crimp of the required strength.

                        You do NOT know that unless it has been tested. And, you should know the effect of small variances from that crimp shape and height, so that you are sure of your tolerance zone.

                        If the crimp is the right height, bit NOT width, then you don't know how the metal flowed. The crimp is presumed defective.

                        If you are just doing tent cable, maybe that's good enough. But for anything important, a "high confidence" crimp, trying to do it with home-made crimping dies that are not made to dimension, and are not known to produce a good crimp, is just plain silly when the right, proven dies etc are available at what is, in the long run, a low cost.

                        If you don't care, or if you can test the strength, well, fine, do what you like. You've been told, so it's now on you. You cannot claim you didn't know.
                        Last edited by J Tiers; 04-17-2016, 11:30 AM.
                        1601

                        Keep eye on ball.
                        Hashim Khan

                        Comment


                        • #13
                          Aircraft and wire rope have standards for the swage.There are military and civilian standards for terminations in both.The use of a go/no go gauge insures the finished swage conforms to the spec regardless of manufacture.A proper swage is gauged as fitting the go gauge with no flash or ovality present.

                          Think it through,what sort of a disaster would it be if every manufacture had their own spec?Imagine having to inspect and certify terminations in the field with 50 different mfgs and 50 different standards,not pretty or practical.

                          Electrical connections are a different animal entirely and the systems used there have no bearing on terminations made for aircraft or wire rope terminations.
                          I just need one more tool,just one!

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                          • #14
                            In a former life I used to crimp seat belt buckles onto wire cable. We used split hexagonal dies with radiused corners and a 90 ton Ironworker to crimp them. As you can imagine, there is no room for compromise here. The only acceptable tensile test was a broken cable or buckle. My point is that you need to be able to test for your conditions to establish the size and shape of your dies. Bob.

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                            • #15
                              If you want ultimate strength with almost no possibilty make a Flemish Eye. You unwrap 3 out of the 7 outer wire bundles and weave them back togther in the opposite direction. The ferrule then just traps the loose ends. Strength is the same as the cable.

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