Slava 2428 mainspring replacement

[ForgacsV]

Hello Everyone,

So I recently bought a Slava watch with a 2428 movement in a pretty good condition for a very good price.

The watch was running quite slow, but all functions were working properly. After I disassembled the movement, I saw that one out of the two mainsprings was broken.

I tried to search online for mainsprings to this caliber, but I couldn't find a direct replacement, and I'm really not sure how to choose the right piece. So, I would like to ask your help in:

-Could I buy a universal mainspring that I can use to replace the broken spring?
OR
-Should I measure the length and width of the old mainspring, and look for a similar size?
OR

-Something else that comes to your mind?

Thank you for helping me out!
I'm also posting some pictures
 

[Marc]

1 hour ago, ForgacsV said:

Could I buy a universal mainspring that I can use to replace the broken spring?

There isn't really any such thing as a universal main spring.

1 hour ago, ForgacsV said:

Should I measure the length and width of the old mainspring, and look for a similar size?

This is the way to go. You need the height (width), the strength (thickness), and the length. The end is just a standard manual wind end.

The most critical measurement is the height as this will determine how well it fits into the barrel. Then the strength, you should try and get as close to the original as possible, then length which is the least critical.

Then if you go to a site like Cousins UK and input those parameters you should see all of the options that they offer, pick the most appropriate or make a note of the GR number and find an alternative supplier. If you just put in the height and the strength then it will give you all of the different lengths available for those parameters.

[ForgacsV]

Amazing, thank you for the nice explanation and the sourcing site, I will follow your instructions!

[RichardHarris123]

Do you know what caliber it is? 

[Marc]

1 hour ago, RichardHarris123 said:

Do you know what caliber it is? 

I think there may be a clue in the title of the thread

[RichardHarris123]

7 minutes ago, Marc said:

I think there may be a clue in the title of the thread

Oops, how remiss of me. Hehe.  I haven't heard of Slava, so I have learnt something.