Hairspring repair help

szbalogh · September 29, 2016

Here is this Stowa balance assembly. The outer coul of the spring is resting on the internal regulator pin if i set the regulator to good rate in DU and DD positions. It has ~30-40 sec/day gain in PU and the same loss in PD. If i set it to lower rate then the outer coil barely leaving the regulator pin. It should be between them at rest.

If i remove the spring from the balance and mount it on the cock then the collet goes to the point marked with the red circle.

Where and how much to manipulate the spring? I was watching Marks videos and reading the related part in De Carle watch adjusting book but still not get it. I dont want to ruin the watch after working so much with it. Please help!

clockboy · September 29, 2016

This is a good link that explains better than I could. The hairspring should be in the middle of the regulator pins & stay in that position throughout all of the regulation,

http://raulhorology.com/2012/12/the-mark-of-a-true-watchmaker-forming-hairsprings-part-4-pinning-to-the-stud-final-adjustments/

jdm · September 29, 2016

Can you re-pin the hs on the end stud to be an hair longer? That could avoid manipulation of the dog leg which is always a risky proposition.

szbalogh · September 29, 2016

18 minutes ago, clockboy said:

http://raulhorology.com/2012/12/the-mark-of-a-true-watchmaker-forming-hairsprings-part-4-pinning-to-the-stud-final-adjustments/

Thank You! Investigating the description.

12 minutes ago, jdm said:

Can you re-pin the hs on the end stud to be an hair longer? That could avoid manipulation of the dog leg which is always a risky proposition.

Yes, i was thinking about that and excluded as a solution. If i make the HS longer then i need to move the regulator further to keep time and will end up in the smae situation.

jdm · September 29, 2016

The point of having a correct overall hs length, as well the smaller beat error possible is to keep the regulator in the middle of its range. That and a good hs shape, should make so all is good. How is the timegrapher picture?

szbalogh · September 29, 2016

3 minutes ago, jdm said:

How is the timegrapher picture?

This was at the beginning:

Then i noticed, that the stud is mounted to low and the HS was not flat. Moreover, the regulator pin was bent. (I think it has to much distance between the pins after reading the description linked by Clockboy. I will reshape that to get hem closer.). Corrected the flatness and straightened the pin and it got better amplitude. Both pictures are dial down, the same is with dial up. But terrible performance if the movement is sideways.

jdm · September 29, 2016

The regulator pin distance is relative to how much the hs is "breathing", again this depends on its shape and amplitude. Personally I woud try a small manipulation of the hs to contrast the sagging when vertical, rather than messing with the regulator pins. But in this case you are doing positional adjustment and that is more an art than science.

oldhippy · September 29, 2016

No matter where the regulator is the hair spring should be able to bounce between the regulator pins and no two coils of hair spring should be touching.

szbalogh · September 29, 2016

Ok, the description above and oldhippy saying that the most important is that the HS ens curve stays perfectly centered between the pins no matter the regulator position. Then i will need to take off the HS and first make sure of this. And then? The collet position can be set by the dog leg 2x 45 degrees bending? And how can i determine the distance between the two bendings? Or just make the bendings and change the degree of them so that the collet get over the jewel?

jdm · September 29, 2016

I wouldn't alter the dog legs. All you have to do is to correct slightly the final curve. If you look on youtube there is a video by perplxr doing that on a running movement.

szbalogh · September 29, 2016

Thank You! I am checking the video. But i am sure that the collet will move even closer to the pins if i bend a bit on the end curve. I will check that at home.

anilv · September 29, 2016

To address the collet being off center, you can try the followoing

a). Manipulate the spring at point A to move the collet in an arc so that it gets centered on the cock.

b). Manipulate point B so that the whole hairspring shifts in the direction of the arrow.

Also check that the spring run from the stud to regulator is consistent, ie if it is in the centre when the regulator is centred, it should be centred when regulator is set to fast or slow.

Enjoy yourself.

Anil

oldhippy · September 29, 2016

Mark has some good videos about hairsprings. You could type into youtube search watch hairsprings and Marks videos will come up including many others. It is best to watch the videos then for me to explain what you should do.

szbalogh · September 29, 2016

7 minutes ago, anilv said:

To address the collet being off center, you can try the followoing

a). Manipulate the spring at point A to move the collet in an arc so that it gets centered on the cock.

b). Manipulate point B so that the whole hairspring shifts in the direction of the arrow.

Also check that the spring run from the stud to regulator is consistent, ie if it is in the centre when the regulator is centred, it should be centred when regulator is set to fast or slow.

Enjoy yourself.

Anil

Thank You! Please show me the references for points A and B

That perplxr guy omit showing the most important manipulation. At 10:25 one can clearly see that the end curve is following the pins. Especially at the stud. And at 11:00 he is showing the already repaired spring. He must have done soemthing at the stud mounting point.

jdm · September 29, 2016

1 hour ago, szbalogh said:

Thank You! Please show me the references for points A and B

That perplxr guy omit showing the most important manipulation. At 10:25 one can clearly see that the end curve is following the pins. Especially at the stud. And at 11:00 he is showing the already repaired spring. He must have done soemthing at the stud mounting point.

I don't know. There is always a bit of assumption and uncovered areas in their videos. Maybe they keep the complete information for the actual students only

szbalogh · September 29, 2016

2 minutes ago, jdm said:

I don't know. There is always a bit of assumption and uncovered areas in their videos. Maybe they keep the complete information for the actual students only

"At 10:25 one can clearly see that the end curve is NOT following the pins. " I also omitted the most important word

Watching Marks video again and again and just realized that his patient has a bending at the stud. It seems that i need to move the regulator next to the stud, make the start of the curve between the pins and then form the proper arc from there.

Shortly, i need to start shaping from the stud.

Now all is clear, but to much coffe for today... lets hope i wont make it worse

szbalogh · September 29, 2016

Here we go. Internal regulator pin pushing hard on the HS.

End curve shaped. At slowest position:

And in fastest position:

The collet was of course way to far from center. The dog leg was made.

Tried a bigger bend... hell nooo

With sharper turns:

Then i noticed that small bending right after the dog leg in the outer coil. Corrected and looking almost good:

Currently it is looking like this:

What do you think? Where should i do more corrections?

Marc · September 29, 2016

Just a thought but I always get suspicious about the point the HS exits the stud. I have sorted out more out of flat and off centre hair springs by tweaking at the stud than anywhere else and I reckon it's because it's the most vulnerable point if the balance cock is handled carelessly or if there is a struggle with the tweezers trying to remove the stud from the mounting.

Looking at your pics it looks to me like the terminal curve spacing (to the next coil) is less at the stud than at the dog leg.

The difference between the red and green circles.

If you slacken the bends at the dog leg it will reduce the spacing at the dog leg, and if you slacken the bends at and just after the stud it will increase the spacing at the stud; in either case you will need to gently reprofile the arc between the two points. Also, it looks as though both approaches should be possible without adversely displacing the collet from the balance pivot, and could even be used to improve this alignment.

What we can't see though is the where the central point between the inner curb pin and the inside of the boot is. As this is the point you need the hair spring to be at, without knowing where that point is it is impossible to say which of the two adjustments is correct, or if you need to do a bit of both, which I suspect is the correct answer.

If you measure the distance between the centre of the balance jewel and the inside of the inner curb pin and carefully draw a circle on a piece of paper with that diameter using a pair of compasses. Place this template onto a piece of cork board and pin the hair spring to it so that the pin goes into the centre of the circle you will be able to use the circle as a template for the terminal curve. You do need to ensure that the collet is held firmly on the centre of the circle.

Edited September 29, 2016 by Marc

szbalogh · September 30, 2016

8 hours ago, Marc said:

Just a thought ...

Thank You for the time and help!

Yes, that end curve has a strange arc but surprisingly following the pin.

Reassembled this morning and set the regulator to ok time in DD position. It is almost out of regulating space. Should i shorten the HS at the stud? That would ruin all of my work Or remove weight from the balance? The staff was repivoted both end so it is possible that weighing more now.

Seems to me that the regulating pins are to far from each other. Or is it ok? As You suggested, first we should come to an agreement with this to make final shaping.

It has nice amplitude now in DD even with much bigger beat error (placed back the stud where it was befor tinkering and have not corrected on the beat yet). But total scrap results in PU, PD and DU. Definitively dirt, since it shows irregular pattern. I will check this after proper cleaning (I had mounted and dismounted the separate parts many times).

Capture_20160930.wmv