Retrofitting a hairspring

[Fred]

Hi everyone,

I'm wondering if it's possible to fit a hairspring from another watch given that the beat, the roller and the collet fit correctly.

Thanks alot

[oldhippy]

Is the movement the same caliber? If yes it should be ok, but the balance will need ajusting. If the answer is no, then forget it. You will have so many problems, timing, beat error ajustment just to name a few. 

[rogart63]

Can be done but takes some tinkering. Easiest is to use the right hairspring . I am doing this with a Eterna watch where i can't find a balance and hairspring.  So i have used a balance from a MST 317 movement . It runs but is running slow. So need to shorten the hairspring a little. This has been a long project that i have worked on for several month. And will probably not run super. But will work okay in the end i think. Right now i am waiting for a longer balance staff . As the 317 was to short. Making the wheel touching the pallet fork bridge. 

[Fred]

46 minutes ago, oldhippy said:

Is the movement the same caliber? If yes it should be ok, but the balance will need ajusting. If the answer is no, then forget it. You will have so many problems, timing, beat error ajustment just to name a few. 

No it's not the same caliber, that would've been somewhat straightforward, I have an Omega 625 and couldn't find an affordable balance cousins UK have it for 325 pounds, I thought maybe I can fit a different hairspring see how it goes.

[Fred]

40 minutes ago, rogart63 said:

Can be done but takes some tinkering. Easiest is to use the right hairspring . I am doing this with a Eterna watch where i can't find a balance and hairspring.  So i have used a balance from a MST 317 movement . It runs but is running slow. So need to shorten the hairspring a little. This has been a long project that i have worked on for several month. And will probably not run super. But will work okay in the end i think. Right now i am waiting for a longer balance staff . As the 317 was to short. Making the wheel touching the pallet fork bridge. 

I'm gonna try it and see, maybe I'll be able to find a donor movement for cheap in the future. Make sure you take pics while working on it, we'll be glad to see them here.

Thanks again

[rogart63]

47 minutes ago, Fred said:

I'm gonna try it and see, maybe I'll be able to find a donor movement for cheap in the future. Make sure you take pics while working on it, we'll be glad to see them here.

Thanks again

I will. Btw look for Tissot 2141 as that is essentially the same movement. Like this ebay 163044591097

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&2&2uswk&Tissot_2141

Edited May 21, 2018 by rogart63

[oldhippy]

What type of balance wheel is it?

[Fred]

1 hour ago, rogart63 said:

I will. Btw look for Tissot 2141 as that is essentially the same movement. Like this ebay 163044591097

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&2&2uswk&Tissot_2141

Thanks Rogart63 that should work and the price is great. I'm gonna grab it.

[Fred]

1 hour ago, oldhippy said:

What type of balance wheel is it?

I don't understand the question but here's a picture.

[clockboy]

12 hours ago, Fred said:

Hi everyone,

I'm wondering if it's possible to fit a hairspring from another watch given that the beat, the roller and the collet fit correctly.

Thanks alot

Yes because I have done this. However manipulation is required.

[oldhippy]

This a Glucydur Balance which cannot be adjusted. The only way of regulating this type when you use a different hairspring is by its length.

[rodabod]

Yes, these smooth-rimmed balance wheels are less flexible when it comes to fitting different hairsprings as there are no screws to attach timing washers, or conversely no screws to remove to lighten. 

You also have to consider the hairspring material as it should be some sort of Elinvar in order for it to have suitable temperature compensation. 

[Nucejoe]

Can be done,

Producing the design; ( desired) frequency is the aim. 

I plan to write and post an article on the forum, a breif explanation of the dynamics of balance wheel, metalurgics of H/S, industrial proccess of H/S production... which I believe shows the way to a repairman's better understanding of what he is doing.

Just needs some time, I am old and lazy.

Regards.

[Nucejoe]

Hi  check this,

www.ofrei.com/page820.html

Regards