Hello from Brazil

[kiyoshi7]

Hi everyone. I've been watching wristwatch revival on YouTube for the past 2 years and decided to take up the hobby. Also because I have a very old wristwatch that belonged to my great grandfather and the man who used to service it retired so I want to learn how to keep it going. Just so you know a bit more, I am a physicist and with sensor calibration and electronics so I am used to small finicky things.

 

I got a cheap pocket watch I think it is a 285 movement. I was imagining I would only need to clean/oil but just my luck I need to replace the balance staff. Which is why I came here. I saw a few videos on replacing the part however I am not sure on where to buy the part. I found a part on ebay called " WATCH PART 1 BALANCER AXIS FOR UNIVERSAL WATCH 14" 285 high WATCH STOCK“ but how do I know if it fits in the watch? here is an image for the movement. I still haven't done anything on it. The watch seems to wind and everything but the balance seems to be good.

 

I have a resin 3d printer and will try to print some tools, in engineering resin, to help replacing the staff as I don't currently have tools to replace the staff ( for me this is part of the fun).

 

Any help and advice is much appreciated.

 

[oldhippy]

Thank you for your introduction and welcome to this friendly forum.

We all look forward to your contributions and continued involvement. 

If there is anything we can help you with don’t be afraid to ask. Nice clear photos can help a lot.

[RichardHarris123]

Hello and welcome from Leeds, England. 

[watchweasol]

Hello and welcome to the forum,    Enjoy

[Nucejoe]

 Once you are sure of the caliber, go on to Dr ranfft website to see the staffs specification.

Another good data base is Mizeni.

Welcome to the WRT forum & 

Good luck

Edited April 4 by Nucejoe

[kiyoshi7]

22 hours ago, Nucejoe said:

 Once you are sure of the caliber, go on to Dr ranfft website to see the staffs specification.

Another good data base is Mizeni.

Welcome to the WRT forum & 

Good luck

Thanks with dr ranfft's site I found the caliber Unitas 285. If I understood the site correctly I need a balance staff: U991. now I will just hunt a place to buy the part.

 

[Nucejoe]

  Now go on to balancestaff.com, select universal and scroll down to universal  linge 14"  find calib 285. This guy sells parts, also diaplays schematic diagram of staffs with list of dimensions for the staff you need.

Many material houses in Europe and USA retail watch parts.

Good luck 

 

 

 

Edited April 5 by Nucejoe

[AndyGSi]

If you got to balancestaffs .com and select Unitas 285 you get the following.

The other option is to look at the Ronda Staff Catalogue which chows it as a 3674.

44 minutes ago, Nucejoe said:

Now go on to balancestaff.com, select universal and scroll down to universal  linge 14"  find calib 285. This guy sells parts, also diaplays schematic diagram of staffs with list of dimensions for the staff you need.

That would be correct if it was a Universal 14" 285

Edit

Just realised yours isn't the Inca so would be a Ronda 2382 (not that's there's much difference)

Edited April 5 by AndyGSi

[kiyoshi7]

On 4/5/2025 at 5:44 PM, AndyGSi said:

If you got to balancestaffs .com and select Unitas 285 you get the following.

The other option is to look at the Ronda Staff Catalogue which chows it as a 3674.

That would be correct if it was a Universal 14" 285

Edit

Just realised yours isn't the Inca so would be a Ronda 2382 (not that's there's much difference)

Thanks I just ordered 2 2382 and some tools to help me take apart the balance without destroying everything lol.

 

Can you tell me how or where to find references for the main spring? Or do I just go by the diameter of the barrel ? I might as well replace the old one.

When the parts arrive I will start another thread talking about the progress. Especially because I plan on 3d printing some basic tools ( with resin) and if they work and can help someone I might as well contribute

[AndyGSi]

There are a couple of sites where you can find the mainspring size.

Emmy also shows a list of possible GR references.

https://www.emmywatch.com/db/mainspring/1_5-0_18-450-15-man/unitas--285/

Ranfft confirms the original size as 1.50 x 15.0 x 0.18 x 450mm.

https://ranfft.org/caliber/10192-Unitas-285

Here in the UK I buy from Cousins which lists the GR43071 being one of the alternatives also shown on Emmy.

https://www.cousinsuk.com/category/filter/unitas-ut

The only real difference is the thickness between the original 0.18mm and the GR 0.175mm which
is best practice as  you don't want to use a thicker (stronger) spring in an old movement.