Closing New Mainspring Around Arbour

[jdrichard]

Here is the situation. I am replacing a Mainspring for a ladies Squale (1974) diver watch. The loop for the mainspring is much bigger than the Arbor as shown in the picture. I have already broken a new Mainspring and this is the second one. So what is a safe method of closing the loop of the mainspring so it fits the Arbor ? This is a small barrel that it fits into and my current mainspring pliers do not fit into the spring. HELP!

 

 

Sent from my iPhone using Tapatalk Pro

[Federico]

Well here is what I do..not sure if it is correct or not but here goes. If it is one of the new Swiss alloy mainsprings I usually have trouble fitting them into bergeon mainspring winders since the inner coil is always huge and the barrel arbor is always so thin, so what I do is I heat the tip slightly over a small candle flame until it turns straw brown. It takes probably about 1 second total as it changes fast. I will go back and forth a couple times in small amounts of heat exposure (half inch over flame not directly on) just to make sure I do not heat it too much (The moment it goes red hot its a gonner). Once I get the right color I then let it cool slowly. This usually takes the brittleness out and makes it much stronger and stiffer yet still springy. The new attributes allow me to bend the inner coil with some parallel action coiling pliers with no worry.

This has worked for me perhaps it will work for you. Experiment with your broken springs first to get it right. I broke about 4 before I started experimenting with the broken springs and figured out the above.

This method does not work with the old blue steel springs.

Good luck and I look forward to reading what other people have to say.

[anilv]

You need to get the correct mainspring.

Federico's method will work as you're removing the temper but I think that it will fail sooner.

Anilv

 

[oldhippy]

That is not the correct spring for the movement cal number, you need to get the right one ask your supplier. Heating this type of spring is not recommended they are not made to be tampered with; they are made in such a way as to fit.

[Watchtime]

@jdrichardI am happy to see if I have the correct spring for you, just let me know.

[Federico]

How do you all know by sight that the spring is incorrect? (Would love to learn this skill) I would assume the OP purchased the correct spring. I ask because I can never get the Swiss alloy spring onto a new bergeon mainspring winder arbor even if I am using the correct sized spring and winding barrel. I always have to fiddle with it to fit. This is not the case if I use a NOS blue steel spring. I hope the OP does not mind me asking this question in his post but it seems very relevant.

 

 

Sent from my iPhone using Tapatalk

 

[Federico]

You need to get the correct mainspring.
Federico's method will work as you're removing the temper but I think that it will fail sooner.
Anilv
 

Really?
It's not being heated past critical point that would as you said remove the temper. If anything it would be tempering it as you stay well under the critical point that would soften the spring. This method increases hardness, strength and reduces brittleness.

Would love to hear more of your thoughts. If the OP does not mind.

[jdrichard]

[mention=1704]jdrichard[/mention]I am happy to see if I have the correct spring for you, just let me know.

This watch is a woman's Squale Diver


Sent from my iPhone using Tapatalk Pro

[jdrichard]

That is not the correct spring for the movement cal number, you need to get the right one ask your supplier. Heating this type of spring is not recommended they are not made to be tampered with; they are made in such a way as to fit.

Now you've scared the crap out of me. Already bought the spring, but I get your point.


Sent from my iPhone using Tapatalk Pro

[jdrichard]

You need to get the correct mainspring.
Federico's method will work as you're removing the temper but I think that it will fail sooner.
Anilv
 

Most likely correct, already down 25 bucks for 2 mainsprings


Sent from my iPhone using Tapatalk Pro

[jdrichard]

Well here is what I do..not sure if it is correct or not but here goes. If it is one of the new Swiss alloy mainsprings I usually have trouble fitting them into bergeon mainspring winders since the inner coil is always huge and the barrel arbor is always so thin, so what I do is I heat the tip slightly over a small candle flame until it turns straw brown. It takes probably about 1 second total as it changes fast. I will go back and forth a couple times in small amounts of heat exposure (half inch over flame not directly on) just to make sure I do not heat it too much (The moment it goes red hot its a gonner). Once I get the right color I then let it cool slowly. This usually takes the brittleness out and makes it much stronger and stiffer yet still springy. The new attributes allow me to bend the inner coil with some parallel action coiling pliers with no worry.
This has worked for me perhaps it will work for you. Experiment with your broken springs first to get it right. I broke about 4 before I started experimenting with the broken springs and figured out the above.
This method does not work with the old blue steel springs.
Good luck and I look forward to reading what other people have to say.

I now have two practice mainsprings to try this on so what the heck. But I thing, as recommended, I need the right Mainspring.


Sent from my iPhone using Tapatalk Pro

[rodabod]

I would take a pair of round-nosed pliers to it. The hook end is already anealled usually. The first full wind will help to set the first wrap in position. Can try this, wind down, and then inspect when the spring is relaxed. 

[digginstony]

Really?
It's not being heated past critical point that would as you said remove the temper. If anything it would be tempering it as you stay well under the critical point that would soften the spring. This method increases hardness, strength and reduces brittleness.

Would love to hear more of your thoughts. If the OP does not mind.

Tempering is far more desirable than case Hardening but is normally done over a long period of time as opposed to bringing steel to cherry red and dipping into solution (Even Water). I think your conclusion is sound but it seems you are making the alloy more pliable by gentle heat.
The term alloy is deceptive anyway as steel is an alloy derived from iron. I have no idea of the compounds used in Swiss alloy it may have chromium and nickle and something even non ferrous but couldn't say. Interesting if anyone Knows?
Anliv comments are also valid as some compounds when heat applied can reverse the hardening effect it really depends on the constituents that your dealing with.
Over heating will cause the metal to crystallise and will fail long before its expected stress level.
Ive never had a mainspring I haven't had to fiddle with a bit in a mainspring winder.
I wouldn't of thought what you're doing would have any negative effect on the hardness of the spring yet if no heat applied you're saying the spring can snap?
When case Hardening steel it's most pliable in its cherry hot state and only forms a hard layer during the cooling process. You may be reaching a happy medium with what your doing and I wouldn't have any concerns unless springs started snapping on me [emoji4]


Sent from my SM-T585 using Tapatalk

[Federico]

Tempering is far more desirable than case Hardening but is normally done over a long period of time as opposed to bringing steel to cherry red and dipping into solution (Even Water). I think your conclusion is sound but it seems you are making the alloy more pliable by gentle heat.
The term alloy is deceptive anyway as steel is an alloy derived from iron. I have no idea of the compounds used in Swiss alloy it may have chromium and nickle and something even non ferrous but couldn't say. Interesting if anyone Knows?
Anliv comments are also valid as some compounds when heat applied can reverse the hardening effect it really depends on the constituents that your dealing with.
Over heating will cause the metal to crystallise and will fail long before its expected stress level.
Ive never had a mainspring I haven't had to fiddle with a bit in a mainspring winder.
I wouldn't of thought what you're doing would have any negative effect on the hardness of the spring yet if no heat applied you're saying the spring can snap?
When case Hardening steel it's most pliable in its cherry hot state and only forms a hard layer during the cooling process. You may be reaching a happy medium with what your doing and I wouldn't have any concerns unless springs started snapping on me [emoji4]


Sent from my SM-T585 using Tapatalk

Yes the spring will snap if made to hug the arbor without the method I described. It will only bend so much before breaking. I took out my test spring after reading the above comments and really started to abuse it as much as I could think of. Twisting the end bending it back and forth many times. It was very strong I am applying quite a lot of force to do this as it has become much stronger. yet it is able to bend in on itself without snapping. I suppose time will tell how well or horrible this actually is.

I completely agree that Anliv's comment has merit as it is completely true with the old blue steel springs I tried it on. But for some reason it has a slight different effect with the Swiss alloy using gentle heat. Well perhaps after a couple months/years I can report back on the method and get some sort of conclusion.


Sent from my iPad using Tapatalk

[digginstony]

Yes the spring will snap if made to hug the arbor without the method I described. It will only bend so much before breaking. I took out my test spring after reading the above comments and really started to abuse it as much as I could think of. Twisting the end bending it back and forth many times. It was very strong I am applying quite a lot of force to do this as it has become much stronger. yet it is able to bend in on itself without snapping. I suppose time will tell how well or horrible this actually is.

I completely agree that Anliv's comment has merit as it is completely true with the old blue steel springs I tried it on. But for some reason it has a slight different effect with the Swiss alloy using gentle heat. Well perhaps after a couple months/years I can report back on the method and get some sort of conclusion.


Sent from my iPad using Tapatalk

Yes please report back with any data, as and when. Very interesting

Sent from my SM-T585 using Tapatalk

[jdrichard]

I would take a pair of round-nosed pliers to it. The hook end is already anealled usually. The first full wind will help to set the first wrap in position. Can try this, wind down, and then inspect when the spring is relaxed. 

It is the size of the Arbor that is the problem. Very very small


Sent from my iPhone using Tapatalk Pro

[jdrichard]

How do you all know by sight that the spring is incorrect? (Would love to learn this skill) I would assume the OP purchased the correct spring. I ask because I can never get the Swiss alloy spring onto a new bergeon mainspring winder arbor even if I am using the correct sized spring and winding barrel. I always have to fiddle with it to fit. This is not the case if I use a NOS blue steel spring. I hope the OP does not mind me asking this question in his post but it seems very relevant.
 
 
Sent from my iPhone using Tapatalk
 

I have changed many a spring and usually need to bend it a bit to wrap around the Arbor and get hooked


Sent from my iPhone using Tapatalk Pro

[rodabod]

11 hours ago, jdrichard said:

It is the size of the Arbor that is the problem. Very very small


Sent from my iPhone using Tapatalk Pro

I think I understand that. But have you tried taking a fine set of round nose pliers to reduce the radius of the first wind of the mainspring?

You presumably can't change the arbor unless you want to turn a new one. 

[jdrichard]

I think I understand that. But have you tried taking a fine set of round nose pliers to reduce the radius of the first wind of the mainspring?
You presumably can't change the arbor unless you want to turn a new one. 

Don't have fine round nose pliers


Sent from my iPhone using Tapatalk Pro