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Spring making, coils folding over... help?

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  • Spring making, coils folding over... help?

    Hi everyone,
    I'm hand making long springs. And I'm having trouble - they wind well but as the spring gets longer, it becomes as if it's trying to fold itself over. I don't know why, and I would really appreciate any help with this issue!

    Here is a video of the phenomena:
    https://www.youtube.com/watch?v=yJDu...ature=youtu.be

    Many thanks!

  • #2
    Is the raw stock you're using feeding off of a spool of some sort? I'm wondering if you unintentionally introducing a kink, or twist in the wire as you feed it. Can you post a picture or video of the setup?

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    • #3
      Originally posted by tom_d View Post
      Is the raw stock you're using feeding off of a spool of some sort? I'm wondering if you unintentionally introducing a kink, or twist in the wire as you feed it. Can you post a picture or video of the setup?
      I'm using a spool like this:
      https://www.howardpianoindustries.co...wire-canister/

      Also this has happened multiple times. So it doesn't seem to be a one off accident. It's as if some kind of force is building up coil by coil somehow.
      I did have the canister hanging on something, so it could turn around as the wire got pulled out of it. But perhaps some kind of forces were accumulating there somehow...?

      Anyone ever encountered this flappy spring thing before, coils folding over when tension starts to be applied instead of the coils remaining perpendicular to the axis of the spring? If so, what were the causes there? Even if they are not identical here, knowing what can cause this might help us identify the cause in this case, or the principle behind the phenomenon.

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      • #4
        Originally posted by MakingThings View Post
        Hi everyone,
        I'm hand making long springs. And I'm having trouble - they wind well but as the spring gets longer, it becomes as if it's trying to fold itself over. I don't know why, and I would really appreciate any help with this issue!

        Here is a video of the phenomena:
        https://www.youtube.com/watch?v=yJDu...ature=youtu.be

        Many thanks!
        I couldn't see very much in the video and could hardly hear the explanation either, but it looks to me as if some of the original coiling is being transferred to the smaller spring coil. Rather than having the feedstock coil lying flat and pulling it from the center of the coil, as the case appears to do, that coil should be able to rotate (in its plane) about its center as the material feeds off tangentially from the outside. Think of the similarity to the reverse, when coiling a stiff extension cords that already has a set; if not done correctly, you will find some loops will try to twist around, perhaps into figure 8's, instead of all lying flat.

        Another thing which comes to mind its that, if the tensioner were putting more drag on one side of the wire as it feeds onto the mandrel, that could induce slight stretching and strain which could cause the same problem.
        Last edited by CreakyOne; 07-16-2018, 06:00 PM.

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        • #5
          What or how are you tensioning the wire? For winding around a form like this maintaining the tension is critical. And keep in mind that as it's coming out the center of the container it's also putting some twisting into the wire. But you're not getting any issue with the over winding until later. And the twisting would be stable after only a few turns. So I tend to think it's the way you tension the wire and the feed being a touch slower than ideal. If the feed rate does not match the diameter of the wire then it's going to lag behind and finally "relieve" the slowly growing lag amount with an overwound turn or two before it goes back to smoothly laying the turns for a while.

          There may be another factor at play here too. That's a fairly fine wire on a larger diameter form. So there's a LOT of spring back growth that is going to occur. And I found that the spring can become distorted if the coiling on a close wound spring of this sort is not done evenly. That may be why you're getting some of the coils jumping over each other.

          You're also asking about why the spring is pulling the coils to an angle. Yet the starting wire is still attached. It will naturally pull to an angle in that case. And in fact I don't see anything wrong with how it behaves. remove the starting end and pull while evenly holding both sides of the last coil and I'm sure it'll pull straight and evenly. The only issue I see is where the coils jumped each other which likely occurred during the tension release.

          All I can suggest for a trick to avoid the coils jumping over each other is at the end of the winding HOLD the last turns tight and cut away the wire. Then using two hands draw out the length while letting go and keep drawing it out as the spring allows so as you let the spring wind open the coils cannot wrap over each other.

          Another possible reason they are wrapping over each other is that the coils may not be the same size. Which again comes back to the question of how you are holding tension in the wire while winding on. If it's not consistent to a very high degree the coils won't all be the same size. And with a close wound tension spring you can end up with the inbuilt tension causing a larger coil to jump over a smaller coil.

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