alloy vs steel mainspring question

klokwiz

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hi, at the risk of asking a silly question ( i know there are none) but I have been scanning the spring posts and have not found my answer. Is there any discernable difference in the rating of a watch if changing from a blued steel MS to an alloy. It seems to me that the alloys are stronger than the blue but this is really only my impression. So simply stated can a stronger spring make a 12, 16 or 18 size watch run fast? Joe.
 

Skutt50

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So simply stated can a stronger spring make a 12, 16 or 18 size watch run fast?
In theory - no. In real life - Yes.

The watch should not run fast however, the stronger mainspring will cause a bigger swing. A newly serviced watch, with a mainspring that is a bit too strong, may start to knock. This means that the balance swings all the way to a point when the impulse jewel will hit the pallet fork from behind. This will upset the timing and the watch may run fast.
 

gmorse

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Hi Joe,
Is there any discernable difference in the rating of a watch if changing from a blued steel MS to an alloy. It seems to me that the alloys are stronger than the blue but this is really only my impression.
I don't think there's much in it, but have a look at David Boettcher's website on mainsprings.

Regards,

Graham
 

John Runciman

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So simply stated can a stronger spring make a 12, 16 or 18 size watch run fast?
it's an interesting question that has technical problems?

The watch should not run fast however, the stronger mainspring will cause a bigger swing. A newly serviced watch, with a mainspring that is a bit too strong, may start to knock. This means that the balance swings all the way to a point when the impulse jewel will hit the pallet fork from behind. This will upset the timing and the watch may run fast.
the term for this is Rebanking. and I have a video blow that explains it.


so if we exclude Rebanking. because it's only at the extreme how much effect is amplitude have on timekeeping? then other minor little issue with your question is are the mainsprings the exact same shape? So the only thing changed is the strength not the shape which conceivably will produce slightly different power curve's?

then a word for the day because we need it for the rest of the discussion isochronism found at the link below.

Isochronous timing - Wikipedia

Is there any discernable difference in the rating of a watch
have not found my answer
I have a suspicion not finding your answer is the answer? in other words is a very common thing the change from blue steel to the white Springs. There's also another ongoing problem of their used to be more mainspring strengths and there are now so conceivably you can't get the strength to you want but yet we do not see the continuous ongoing discussion of how I solve timekeeping problems because my mainspring is too strong?

I was thinking about reference material I have any reference to changing the mainspring to something weaker or mainspring issues and what is the issue? If you look at the older Elgin parts Log you'll notice that they had weaker mainsprings. I have a reference that explains about how the factory operated so when are looking at the amplitude if it was too much to a go back to the spring department where that swap with the barrel that had less power. I'm pretty sure I've seen Rolex has different strength mainsprings probably for the same issue. Omega has a reference to if you have too much power you put heavier oil on the balance pivots starting with one pivot then the other. If that doesn't work you're supposed to get a new mainspring barrel. So all those examples there is no reference to timekeeping but there is a reference to too much amplitude.

there's other things that come into play like the regulator pins. What effect do they have on timekeeping? Ideally the hairspring is supposed to be centered between the pins you get interesting timekeeping issues if it's not not always a big issue though. Then if the pins are spaced too far apart you'll definitely see an issue because of amplitude. That would mean changing the mainspring would cause an issue but that's more of a the watch needs you properly adjusted issue.

Then just to show isochronism affects manufacturing information sheet for the 6497 basically modern Swiss pocket watch I snipped out a section. There is two separate columns because there's two different grades of the watch. The lower grade they time in only two positions the better grade and three positions. so this particular case they tell us what the effect of amplitude over 24 hours worst-case for this watch should be.

6497 timing.JPG
 

DeweyC

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hi, at the risk of asking a silly question ( i know there are none) but I have been scanning the spring posts and have not found my answer. Is there any discernable difference in the rating of a watch if changing from a blued steel MS to an alloy. It seems to me that the alloys are stronger than the blue but this is really only my impression. So simply stated can a stronger spring make a 12, 16 or 18 size watch run fast? Joe.
Joe,

Years ago I had several thousand mainsprings made by Schwab Feller (yes, the number is correct). I visited the factory in 2010 and talked with the owners. At least their mainsprings are formulated to yield the same energy curve as a blue spring. The Swiss being Swiss; I would expect this to hold true across other makers.

The other point of note is that the Teflon-coated springs do not require grease. It will not harm them, but it is unneeded.

Finally, the new springs are "baked" with the OD for the barrel arbor and this end is not "soft". This means there is very little lattitude for arbors of a different size. I actually had to send arbors for the springs I had made.

As John pointed out above, a faster rate from a mainspring change indicates rebounding from over amplitude. A precision watch will give the same rate from an amplitude of 220 degrees to over 300 degrees so the energy itself is not an issue.

I replace all blue mainsprings. First, they are fatigued and provide insufficient power. Second, they are fatigued and prone to breakage, especially after being removed and replaced into the barrel. Generally after about 2 months. Depending on the piece, this can cause extensive damage since it tends to happen when the spring is fully wound.

Mainsprings are the weak link in watch service. Good timing cannot be achieved without a good mainspring. And in my view, a watch is not a watch unless it performs as originally intended.

It has reached a point where I now weld new ends onto otherwise correct mainsprings in order to fit the specific barrel.
 

Kenny S.

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I replace all blue mainsprings. First, they are fatigued and provide insufficient power. Second, they are fatigued and prone to breakage, especially after being removed and replaced into the barrel. Generally after about 2 months. Depending on the piece, this can cause extensive damage since it tends to happen when the spring is fully wound.
This sounds like good advice. I have a lot of work to do.

It has reached a point where I now weld new ends onto otherwise correct mainsprings in order to fit the specific barrel.
How do you do this? My guess is with the band saw welder on the Do-All saw? But this might have too much power for a MS.
 

Al J

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At least their mainsprings are formulated to yield the same energy curve as a blue spring.
Do you have information on how this was achieved? Was this through material selection, size changes, thermal treatments?

Cheers, Al
 

DeweyC

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This sounds like good advice. I have a lot of work to do.


How do you do this? My guess is with the band saw welder on the Do-All saw? But this might have too much power for a MS.
Look up dental welders on ebay. All it is is a high amp 5 VAC transformer, but the trick is the clamping mechanism. They used to be under $100; but it looks like the used ones are pretty much gone or exported. the new ones will do the job; but are not cheap.

The original ones (Rocky MTN) had no electronics and work perfectly.
 
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DeweyC

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Do you have information on how this was achieved? Was this through material selection, size changes, thermal treatments?

Cheers, Al
Hi Al.

No, just what I was told. They were not especially willing to show me around. I could not go into the manufacturing area for example. Even though I brought them a bottle of GOOD wine.
 

Al J

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Hi Al.

No, just what I was told. They were not especially willing to show me around. I could not go into the manufacturing area for example. Even though I brought them a bottle of GOOD wine.
Okay thanks. Have you confirmed by measurements that the sizes were not altered from the blued springs?

Cheers, Al
 

gmorse

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Hi Dewey,

Did these alloy springs have the pronounced 'S' curve in the outer section?

Regards,

Graham
 

praezis

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It seems to me that the alloys are stronger than the blue but this is really only my impression.
i will answer with some data as a change.
"Alloy" is often used but is a wishy-washy term. Modern mainsprings are available from Inox (lower cost) or from Nivaflex (higher cost, about 3x Inox).

Ok, I had to look it up:
Torque of the barrel M ~ E x I
E= E or Young's modulus
I= moment of inertia (with physical dimensions of spring, e.g. s^3)
Means, influence of E on torque ("strength") is direct (linear).

My source (Prof. Glaser: Uhrentechnik) mentiones:
E, springsteel, texture rolled: 225
E, Inox: 190 - 210
E, Nivaflex: 225

Schwab-Feller gave me 210 for Inox springs.

So, just regarding its material, Inox springs (alloy!) are a bit weaker than steel springs.
Nivaflex springs (alloy!) are equal or lightly stronger than steel springs.

Hope, this helps,
Frank
 
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Al J

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i will answer with some data as a change.
"Alloy" is often used but is a wishy-washy term. Modern mainsprings are available from Inox (lower cost) or from Nivaflex (higher cost, about 3x Inox).

Ok, I had to look it up:
Torque of the barrel M ~ E x I
E= E or Young's modulus
I= moment of inertia (with physical dimensions of spring, e.g. s^3)
Means, influence of E on torque ("strength") is direct (linear).

My source (Prof. Glaser: Uhrentechnik) mentiones:
E, springsteel, texture rolled: 225
E, Inox: 190 - 210
E, Nivaflex: 225

Schwab-Feller gave me 210 for Inox springs.

So, just regarding its material, Inox springs (alloy!) are a bit weaker than steel springs.
Nivaflex springs (alloy!) are equal or lightly stronger than steel springs.

Hope, this helps,
Frank
Thank you for the useful data.
 

klokwiz

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I'm impressed with the large and knowledgeable response this has gotten. As a practical matter My 924 hamilton which I have posted elsewhere due to a rating issue, just got a NOS blue spring. It originally was inop due to a broken staff. with that repair being what i feel was a sound cleaning and repair the watch ran 90 secs fast. I had replaced the set old blue spring with a "alloy" during the repair process. seeing no credible reason watch was fast I decided to replace alloy with NOS blue steel to see what happened. There is no discernable difference in the watches rate it is still 90-100 seconds fast. So my question: is the new alloy making this watch run fast appears to be a NO. I will be looking closer to see if it is "re-banking". Joe.
 

DeweyC

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i will answer with some data as a change.
"Alloy" is often used but is a wishy-washy term. Modern mainsprings are available from Inox (lower cost) or from Nivaflex (higher cost, about 3x Inox).

Ok, I had to look it up:
Torque of the barrel M ~ E x I
E= E or Young's modulus
I= moment of inertia (with physical dimensions of spring, e.g. s^3)
Means, influence of E on torque ("strength") is direct (linear).

My source (Prof. Glaser: Uhrentechnik) mentiones:
E, springsteel, texture rolled: 225
E, Inox: 190 - 210
E, Nivaflex: 225

Schwab-Feller gave me 210 for Inox springs.

So, just regarding its material, Inox springs (alloy!) are a bit weaker than steel springs.
Nivaflex springs (alloy!) are equal or lightly stronger than steel springs.

Hope, this helps,
Frank
I do love data!
 

Kenny S.

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So my question: is the new alloy making this watch run fast appears to be a NO. I will be looking closer to see if it is "re-banking". Joe.
Joe, if the hairspring is slightly magnetized, it can cause the watch to run fast. Also, if during the cleaning, oiling and re-assembly process any oil got in contact with it, this would have the same effect.

--Kenny
 

klokwiz

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Kenny,

Thanks, I will demagnetize as a precaution before making any changes to the watch. And yes i have seen some really oily balance springs interesting how that works (or does not) and yes even small amounts are problematic.

Joe
 
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