Spring making, coils folding over... help?

MakingThings

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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:

Many thanks!
 
I think I understand what's going on and you can do an experiment to test it.

In your video you're pleased with the behavior of the left end of the spring. Correct?
As an experiment, remove the spring from the mandrel and re-install it the other way around (swap left and right). Be sure to attach the new right end of the coil to the equipment as shown in the video.

I suggest the "folding over" is due to that end of the coil being anchored to the machine.

Let us know what you find out.
 
I think I understand what's going on and you can do an experiment to test it.

In your video you're pleased with the behavior of the left end of the spring. Correct?
As an experiment, remove the spring from the mandrel and re-install it the other way around (swap left and right). Be sure to attach the new right end of the coil to the equipment as shown in the video.

I suggest the "folding over" is due to that end of the coil being anchored to the machine.

Let us know what you find out.
Thanks, and, sorry for not explaining better. This is the same when the spring is free, not attached. It was only attached there because I had just made it. And yes, the behaviour on the left is what I want - the coils all stay with their circular plane perpendicular to the axis of the spring. As it progresses (to the right side), they have an increasing tendency to want to flip so that their plane is parallel to the axis of the spring when tension is applied... until enough tension is applied to make the planes go perpendicular again and it looks 'normal'.
 
There is a book on spring making in the Workshop Practice series, as well as a very good chapter in the Atlas Manual of Lathe Operation on winding springs that features a lot of useful stuff like calculating feed rates in it. I can see that your winding jig is not capable of controlling twist while winding. This is where feeding your wire off of your tool post comes in useful. It might be worth looking those two books up. Both of them are on the download section of this site, which, as of late, is now closed to peasants and available only to site sponsors. Anyway, after watching your video I think you should take a trip down the rabbit hole to visit this lost art.
 
From looking at your video it looks like you are winding over a mandrel vs deflection spring making? How are you holding/feeding the wire as you wind the coil? I've found often lead or trailing angle of the wire as it's fed, as well as and "winding up/twisting" of the feed wire as it is fed out can cause problems as you have shown.
 
How are you holding tension one the wire as it feeds around the mandrel.
This has to be uniform (the tension) and take up has to be uniform (RPMs) without any twisting;
to get the spring to "lay flat" after being removed from the mandrel.
 
I made a pair of discs, one fixed, one sprung, to keep tension on the infeeding wire. But I never made a spring that long....
 
Do you have a device that straightens the coiled wire before forming or are you using pre straightnened wire?
 
Do you have a device that straightens the coiled wire

Never thought of that. The tension on the wire seems to eliminate all previous effects. I have to admit, the tensioner was only used on .009 and .012 wire. Larger wire, (up to .032) I was able to hold in vice grips and pull tight. I did some up to .050 but that required brute force and a bar of steel pressing on the mandrel as the wire bent. most of the springs I make start with about 16" of wire, the tiny ones 36".
 
I can see that your winding jig is not capable of controlling twist while winding. This is where feeding your wire off of your tool post comes in useful.

Most of the machine is not visible in the video. It is hand powered. And I made a wooden 'tool post' which travels along the mandril as the spring is being made, always at the same angle and distance relative to the place each new coil is laid.
When you say "controlling twist", what do you mean? Since I don't know what you mean I can't say if my machine does this or not.

Thanks for the book recommendation, I'll have a look. But I'm also aware that my springs are very unusual and would probably lie outside the usual accepted parameters of how one is supposed to make a spring (they are way more floppy than any spring I would expect anyone else to use, which is precisely why I have had to make them myself - even a spring factory refused to make such unusual springs for me!

Also, I do not see any download section, only a 'video library' section, which when I click on in the menu says "You do not have permission to view this page or perform this action." so I can't even go to that video library page. Is it possible to email it to me through the PM system perhaps?

From looking at your video it looks like you are winding over a mandrel vs deflection spring making? How are you holding/feeding the wire as you wind the coil? I've found often lead or trailing angle of the wire as it's fed, as well as and "winding up/twisting" of the feed wire as it is fed out can cause problems as you have shown.

Sorry I do not know the meaning of 'deflection spring making'. I am winding the wire by hand (turning the mandril with a handle) onto the mandril, with the tension kept fairly regular by <constant turning speed more or less> and <a kind of wooden clamp giving relatively constant friction to the wire a couple of centimetres before it meets the mandril>. That tension system, clamp we could call it maybe, travels up the mandril so it always at he same angle and distance. But, the more coils that are laid, gradually the wire seems to accumulate some kind of forces that make it start to fold over, as you can see on the right side of the spring in the video.

Could you say more about ""winding up/twisting" of the feed wire as it is fed out"? I experimented with different angles at which the wire leads onto the mandril, and found some kind of balance between not too flat and not too steep that seemed to keep the coils tight in the finished spring - going outside that balance seemed to make the coils too loose when finished, not holding together like a normal 'tension spring'. Since the angles were fine for the left side of the spring, does this not imply that this variable is not to blame for the gradual increase in tendency to fold over, as the spring length increases? Or....?

The main variable that came to my mind as a possibility was the wire feed, maybe an issue with how the wire is coming out of the canister? I am using wire around 0.8mm to 1mm (I forgot exactly which gauge for the spring in the video). Good piano wire. This is a pic of the type of canister:
https://www.howardpianoindustries.com/piano-music-wire-canister/

Does anyone have any pics or diagrams of how best to set up the canister for this? Or maybe to abandon the canister for something else if need be? I had it basically hanging, so it could rotate relatively freely as the wire was pulled out of it. Smaller springs no problem, but, for bigger springs, could this be where some kind of forces are being accumulated?


How are you holding tension one the wire as it feeds around the mandrel.
This has to be uniform (the tension) and take up has to be uniform (RPMs) without any twisting;
to get the spring to "lay flat" after being removed from the mandrel.

Thanks for the question - as it was similar to others I think this has now been answered above.

Do you have a device that straightens the coiled wire before forming or are you using pre straightnened wire?
No. But would that really cause this problem?
 
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