Spiral spring.

[Graham_Wright]

I have made hundreds of helical springs in hard drawn phosphor bronze wire winding them in a lathe on a mandrel.
I now need a spiral spring (like a clock escapement spring) that I can then extend into a cone shape.
I've tried winding as before but between cheeks to cause each turn to wind on top of its predecessor but without success. I've also tried to form one by hand working along the length progressively slightly straightening each turn. Close but not close enough.

Any suggestions please? The wire is 2mm diameter.

 

[Freebee]

youtube!!

 

[ean_p]

I have made hundreds of helical springs in hard drawn phosphor bronze wire winding them in a lathe on a mandrel.
I now need a spiral spring (like a clock escapement spring) that I can then extend into a cone shape.
I've tried winding as before but between cheeks to cause each turn to wind on top of its predecessor but without success. I've also tried to form one by hand working along the length progressively slightly straightening each turn. Close but not close enough.

Any suggestions please? The wire is 2mm diameter.

Would it work better with a 'flat' wire as opposed to round ?

 

[Graham_Wright]

youtube!!

Fascinating character and fascinating man cave!
Unfortunately, not relevant. The device is to wind and unwind an existing spring not make one.

 

[Poignard]

How about turning a cone-shaped wooden mandrel and winding it on that?

 

[Graham_Wright]

How about turning a cone-shaped wooden mandrel and winding it on that?

That is on the list of possibles.
I think the wire would need to climb the cone to keep it stable.
It is a bit of a pain to turn a tapered mandrel. It would be better if the mandrel was then threaded but that is an even bigger pain!

 

[Poignard]

Something like a clock/watch fusee?



What size is this spring going to be?

 

[Plum]

I have made hundreds of helical springs in hard drawn phosphor bronze wire winding them in a lathe on a mandrel.
I now need a spiral spring (like a clock escapement spring) that I can then extend into a cone shape.
I've tried winding as before but between cheeks to cause each turn to wind on top of its predecessor but without success. I've also tried to form one by hand working along the length progressively slightly straightening each turn. Close but not close enough.

Any suggestions please? The wire is 2mm diameter.

Why did the winding between cheeks then pulling the centre out not work?

Www.solocoastalsailing.co.uk

 

[Graham_Wright]

Getting there!
The kink in the middle is where the end of the wire is poked through one of the cheeks which has a 2mm hole through it.
I'll try drilling through the boss for the next attempt.

 

[Poignard]

Not a bad effort but wire forming pliers like these of mine would help.

 

[penfold]

How about turning a cone-shaped wooden mandrel and winding it on that?

That's the obvious path if creating a spiral and then extending it is failing; presumably torsional failure through excessive strain?

 

[Graham_Wright]

That's the obvious path if creating a spiral and then extending it is failing; presumably torsional failure through excessive strain?

No failure on extending. 2mm hard drawn phosphor bronze!

 

[Graham_Wright]

Not a bad effort but wire forming pliers like these of mine would help.

View attachment 153525View attachment 153526

I never knew such a machine existed - thanks. Pair ordered.

 

[Poignard]

I never knew such a machine existed - thanks. Pair ordered.

There are two variants, one for tight bends and the other for shallower bends.

 

[Graham_Wright]

There are two variants, one for tight bends and the other for shallower bends.

Latest attempt on a tapered arbour,



Not good enough as it has to collapse completely flat. Need a faster taper.

 

[Poignard]

Latest attempt on a tapered arbour,


View attachment 153647
Not good enough as it has to collapse completely flat. Need a faster taper.

You're getting there!

One of these days you might let us into the secret of what it's for!

 

[Graham_Wright]

You're getting there!

One of these days you might let us into the secret of what it's for!

Guesses welcomed!

 

[Poignard]

Guesses welcomed!

'
It's an anniversary present for your wife

 

[penfold]

Latest attempt on a tapered arbour,


View attachment 153647
Not good enough as it has to collapse completely flat. Need a faster taper.

Promising but needs fewer TPI; are you using power feed on the saddle or is it by hand?

 

[Daydream believer]

Why not place 2 No 10mm discs on a shaft, One disc with a thin 2mm shoulder to keep the 2 mm gap. The shaft made from a bolt. The 2 discs held by a nut wound up tight. . A longitudinal slotted hole in the shaft & shoulder to start off the wire. The head of the bolt held in a 3 jaw chuck. The other end in the tailstock revolving centre.
Now the problem is getting the wire to fit tight to the coils. Fit a piece of steel in the toolpost like a lathe cutter but with 2 small bolts in the side of it held parallel to the lathe centre. The wire passes between the bolts & is kinked, thus bending it . That makes it pre bent & want to curl tightly into the gap between the 2 plates or discs. It also adds friction to keep it tight. When you reach the full diam of the discs stop. Then undo the nut & separate the discs. The slotted hole allows one to draw the wire along the bolt & cut the wire from the slotted hole with a dremel so it can be released from the bolt.
Now one can pull the middle out & form the cone. Obviously it will not be totally small in the middle but you have not said what it is for
I do not know enough about heat treating to know if it should be treated at this stage or not. Others may comment. Also the type of wire will have a bearing on the work. But i believe that as the OP has done spring winding he will have some idea of wire type best suited to the task.