Spring making, coils folding over... help?

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Justin Williams

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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:


Yes, the mandrel size and resultant spring size are correct.
The spring is simple circular shaped coils.
The wire is simple circular cross-section music wire.

More detailed info:
Can you see how at the beginning end (left side in video) the spring behaves normally, but further up (as I wound more coils) when the spring is pulled a bit, instead of it gradually opening up, first it just pulls itself sideways, flattening the spring basically. Like it's getting squashed. Like the plane of the circular coils are trying to align with the axis of the spring, instead of being perpendicular to it.

Only after applying more tension to the spring does it 'pop' back into proper shape, and look and behave like a normal spring (like a slinky for example).

Anyone ever had this problem or know what is causing it and how to fix it?

Many thanks!
 
Last edited:
I'm sure that there is experience on this site to help you but I feel that the spring material already has some stresses built in it before you start winding the spring. If the spring material is stored in a coil that would do it. You may need to uncoil the wire and straighten it under tension.

This is an interesting problem and I'll be following the thread for a solution.
 
Thanks DJP. I'm using 500g coils of wire, feeding out of a canister that can rotate relatively freely. If I cut the straps on the 500g coil when it's not sealed inside the canister, I expect it will explode into a giant tangled pile of spaghetti-like mess. Is there a method of transferring the 500g coil into something else, bigger perhaps, or doing some kind of partial uncoiling? Because to totally uncoil it would require a vast space - the wire is very very long!
 
I can't envisage the quantity of a 500 g coil, so my suggestion may be useless.

To re-coil it could you use something like a garden chemical bucket; start with the open end and make the new coils lie in the bucket so that when finished, the old inside end is what you are starting with. If you do re-coil your wire, you will have to be very careful when using it that you don't pull out more than one coil at a time, probably quite easily done.

To partially straighten the wire to be be used, get two pieces of wood, say 3 x 1 and about 12" long; use 4 nuts and bolts to join the two pieces and pass the wire between the two pairs of nuts and bolts. Adjust the tension on them so that you have to pull the wire you intend to use with some pliers.

Perhaps not on storing wire, but for making springs, have you looked at.
educypedia.karadimov.info/library/springs.pdf
This is a pdf version of the old Bazillion site. Everything you need to know about spring making!

Dave
The Emerald Isle
 
I can't envisage the quantity of a 500 g coil, so my suggestion may be useless.

To re-coil it could you use something like a garden chemical bucket; start with the open end and make the new coils lie in the bucket so that when finished, the old inside end is what you are starting with. If you do re-coil your wire, you will have to be very careful when using it that you don't pull out more than one coil at a time, probably quite easily done.

To partially straighten the wire to be be used, get two pieces of wood, say 3 x 1 and about 12" long; use 4 nuts and bolts to join the two pieces and pass the wire between the two pairs of nuts and bolts. Adjust the tension on them so that you have to pull the wire you intend to use with some pliers.

Perhaps not on storing wire, but for making springs, have you looked at.
educypedia.karadimov.info/library/springs.pdf
This is a pdf version of the old Bazillion site. Everything you need to know about spring making!

Dave
The Emerald Isle
That is an excellent article for making springs, Dave.
Thanks
 
This is a pdf version of the old Bazillion site. Everything you need to know about spring making!

Thanks, I actually have that already. Some parts I found useful.

To re-coil it could you use something like a garden chemical bucket; start with the open end and make the new coils lie in the bucket so that when finished, the old inside end is what you are starting with. If you do re-coil your wire, you will have to be very careful when using it that you don't pull out more than one coil at a time, probably quite easily done.

What is the purpose of re-coiling? Is it so that the coils are bigger, and if so, what advantage does that give? Also, why not just put the 500g coil into a larger (bucket sized?) canister, cut the straps, and it would by itself unwind out to the size of the new canister, right? Is that a good method? One coil is about 100m so we are talking about a lot of wire.

Also once we have bucket sized coils, we still need to feed that to the mandril. (Ha ha, makes it sound like the mandril is a monster :) ) So we would still use the canister type system anyway, wouldn't we? Otherwise how can we feed the wire from the bucket to the mandril? Any pics would be appreciated if this is anything anyone here has done - sometimes much easier to understand ideas visually!

Thanks!
 
Your suggestion about re-coiling. Yes, you could just put the existing coil in the bucket and cut the straps, secure the outer end and shake the bucket a bit to enlarge the existing coils.
How much wire are you intending to use at one time on your spring? My idea of using the two pieces of wood to straighten the wire would be for the length you are about to use, either cut from the coil or pulled out bit by bit. This would mean you have a length of straight-ish wire going onto your mandrel (a mandril is a type of ape!). Perhaps not a lot of use for very long lengths with wire lying about the floor, but I can't think of anything else at the moment for you.

Dave
The Emerald Isle
 
I can't envisage the quantity of a 500 g coil, so my suggestion may be useless.

To re-coil it could you use something like a garden chemical bucket; start with the open end and make the new coils lie in the bucket so that when finished, the old inside end is what you are starting with. If you do re-coil your wire, you will have to be very careful when using it that you don't pull out more than one coil at a time, probably quite easily done.

To partially straighten the wire to be be used, get two pieces of wood, say 3 x 1 and about 12" long; use 4 nuts and bolts to join the two pieces and pass the wire between the two pairs of nuts and bolts. Adjust the tension on them so that you have to pull the wire you intend to use with some pliers.

Perhaps not on storing wire, but for making springs, have you looked at.
educypedia.karadimov.info/library/springs.pdf
This is a pdf version of the old Bazillion site. Everything you need to know about spring making!

Dave
The Emerald Isle
Thank for share !
 
The coils are twisting for the same reason a garden hose is difficult to spool up.
Unless you are rolling out the wire from the spool, every loop unwound from the spool places a one turn axial twist on the wire which ultimately appears on the spring.
 
Since I make springs for my engines on a regular basis and are well familiar with the rat nest formed by a spool of music wire gone wild, I made a 2 parts spool. It has four radial slots, going down all the way to the core (and across), that allows 4 ties to be removed after the spool is secured between the cheeks and ties reinserted and secured before removing one of the cheeks and freeing the spool. The spool mount on the QCTP together with the friction wire feeder.

The OP is experiencing this phenomenon because he is making a long spring requiring several loops from the feed spool. It starts fine but as more and more twists are put on it ends crooked.
 
My way to control music wire for spring making is to use a bucket several inches larger in diameter than the coil and several inches taller. Put the coil in the bucket with the wire end leading out then fill the bucket with clean, dry, fairly coarse play sand or sand blasting sand. Dig down and cut the coil retaining wires, and you can be ready to pull wire from the bucket in a contrlled manner. I have also added a bit of motor oil or spindle oil to the sand to help control rust issues here on the coast
Hope this helps,
Steve
 
The "bucket" method works to keep the spool from "exploding" but unless the bucket is free to rotate without friction it still let the wire twist as it un-spools.
Two different problems:
1) Wire goes haywire because it wants to spring back to the straight shape it had before it was coiled. The ties keep it from doing that.
2) Wire contorts like the garden hose because of the geometry of space. Unless the other end is free to rotate, coiling a noodle place a twist on it. Anybody that winds a long extension cord over his elbows experience that.
 
The "bucket" method works to keep the spool from "exploding" but unless the bucket is free to rotate without friction it still let the wire twist as it un-spools.
Two different problems:
1) Wire goes haywire because it wants to spring back to the straight shape it had before it was coiled. The ties keep it from doing that.
2) Wire contorts like the garden hose because of the geometry of space. Unless the other end is free to rotate, coiling a noodle place a twist on it. Anybody that winds a long extension cord over his elbows experience that.
The wire has taken set in the spool, when feeding to the coiler, you then coil it 90 degrees. This builds up the set, until it exceeds the set of the spring coiling. That is the result.

You need either position the coil in line with the coiling operation, or make a coil straightener, a series of rollers that over bend the coil set, to yield a straight wire, to feed to the coiler.
 
All spring making machines have a wire straightener mounted on the machine before the wire feeder. Often the same applies to power presses for coils of flat strip material. The idea is to start the metal forming with straight material. A little research will show how it is done, as MachineTom says, "...a series of rollers that over bend the coil set, to yield a straight wire, to feed to the coiler.". Coils for industrial use are usually several feet in diameter so the curved set in the wire doesn't usually affect short springs. But the wire straightener will provide consistently straight stock material.
 
Yes. An interesting problem. I can't watch your video, but I assume your one-pound of coiled stock is a fairly small diameter wire. I also assume your final project is a spring having almost no inherent stability (Slinky-like). The problem is evidently that the wire stock contains residual stress (is pre-bent) in a direction other than tangent to the coils in your finished spring. You have to either remove that unwanted stress or herd it into a plane in which it does not cause a problem.

First, I would ensure that the axis of the wire stock coil is parallel to the axis of the forming mandrel. That way, the wire internal pre-stress will have the least effect on the finished product.

Next, in steps, I would try gradually increasing the wire tension on your winding set-up. That may slightly stretch the wire stock enough to re-align all internal wire stress in the desired tangent direction.

Finally, if your final product is an extension spring that is not closed-coil or a compression spring, I would consider winding the spring with essentially closed coils and then plastically deforming (stretching) the spring to its desired final configuration. This may remove the tendency of the final product to "worm". Crude but effective.

As a final last-ditch attempt, before taking a sledge to the project and then enjoying a beer in the shade, I would pass the unleashed stock coil (released in your back yard away from your dog and shrubbery) through a straightening device which plastically deforms the wire slightly in two directions in each of two planes 90 degrees apart. That's what a store-bought sheet or coil straightener does. Personally, if it came to this, I would farm the spring-winding project to Jones Wire & Spring before going to this amount of effort. Somewhat amusingly, Jones' self-proclaimed motto is "We're cheap and fast".

Clark Colby
Coolspring Power Museum
 
Yes. An interesting problem. I can't watch your video, but I assume your one-pound of coiled stock is a fairly small diameter wire. I also assume your final project is a spring having almost no inherent stability (Slinky-like). The problem is evidently that the wire stock contains residual stress (is pre-bent) in a direction other than tangent to the coils in your finished spring. You have to either remove that unwanted stress or herd it into a plane in which it does not cause a problem.

First, I would ensure that the axis of the wire stock coil is parallel to the axis of the forming mandrel. That way, the wire internal pre-stress will have the least effect on the finished product.

Next, in steps, I would try gradually increasing the wire tension on your winding set-up. That may slightly stretch the wire stock enough to re-align all internal wire stress in the desired tangent direction.

Finally, if your final product is an extension spring that is not closed-coil or a compression spring, I would consider winding the spring with essentially closed coils and then plastically deforming (stretching) the spring to its desired final configuration. This may remove the tendency of the final product to "worm". Crude but effective.

As a final last-ditch attempt, before taking a sledge to the project and then enjoying a beer in the shade, I would pass the unleashed stock coil (released in your back yard away from your dog and shrubbery) through a straightening device which plastically deforms the wire slightly in two directions in each of two planes 90 degrees apart. That's what a store-bought sheet or coil straightener does. Personally, if it came to this, I would farm the spring-winding project to Jones Wire & Spring before going to this amount of effort. Somewhat amusingly, Jones' self-proclaimed motto is "We're cheap and fast".

Clark Colby
Coolspring Power Museum
 
There is NO starting stress on the wire except the twist put on by the inadequate un-spooling method. Go out and try to coil or uncoil a 100 feet garden hose by simply pulling it out of the coil. It will twist your arm or self twist into a pretzel.
There is no need to hammer the wire straight or running it through a $9,000 roller straightener.
 
I'm sure tomotore45 and others are right.
The wire twists as you take the coils sideways out of the bucket. It gets one twist for each coil. If the coil diameter in the bucket is, say, 12" diameter, and the wound spring you're making is 1" diam, then the wire will have twisted once every 12 new coils, and is unnoticeable at first. But after, say 240 coils, you will have 10 complete twists which will result in the coils starting lean over - as you have observed.
 
Wire is a pain to wind and unwind tried doing it from a 15 kilo migwire spool to a 5 kilo. What a mess of wire, I think I ended up with 1.5 kg. Before I gave up
 

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