Jewel and balance staf replacement.

[graemeW]

For a break I decided to service a running watch. One of my favourites this. A favre 13 ligne from 1916.

Turns out this isn't so simple either.

seems the lower balance jewel is smashed. It's rubbed in. Also seems to have worn a groove in the balance staff pivot.

I'll try and find a donor that might have a balance, or at least a staff, and a jewel, bit this is problematic.

Don't fancy my chances of finding a main plate to swap as this is pin set from a borgel case. I have seen how rubbed in jewels are replaced, and I know the tools needed to do it.

I've watched videos on replacing balance staffs too, although I don't have a staking set.

So this is another steep learning curve Ive got myself into!

If I can't find a donor, how do you go about finding a jewel. How are they measured? Is it unlikely I'll find something? I'd rather not change to a modern friction fit purely because I've no idea what I'm doing.

The balance staff, are they all completely different or can they be bought by size?

 

I know this is all my own fault. I was warned not to play with antique watches until I know what I'm doing, but I hoped out of 4 of these watches (trench watches, all different movements) I'd be able to get one going. All 4 have serious issues though, even though 3 ran!

I guess this is how it goes with 100 year old watches. I'd expect the same thing playing with any 100 year old mechanical device.

Edited February 2 by graemeW

[AndyGSi]

If it is a Favre 13 then you should be able to check the dimensions.

[graemeW]

16 minutes ago, AndyGSi said:

If it is a Favre 13 then you should be able to check the dimensions.

Showing my inexperience here, so is that a potential universal staff for 13 ligne watches? Or will ronda sell hundreds of staffs for 13 ligne watches and if I measure mine, I might find one that works?

I know in those days swiss manufacturers all bought in parts from suppliers who specialises in certain components.

That would solve one issue.

 

Edit... didn't notice that was listed as favre specific. 

 

Is there a similar situation for jewels? I mean, they all look pretty similar depending on location. The balance jewels in every 13 ligne I've took apart, at a glance, look pretty similar.

I have a spare balance and main plate from a different movement of the same size and date. I wonder what the chances are...

 

Edited February 2 by graemeW

[AndyGSi]

33 minutes ago, graemeW said:

I have a spare balance and main plate from a different movement of the same size and date. I wonder what the chances are...

I'd put it at slim to none.

[graemeW]

Just now, AndyGSi said:

I'd put it at slim to none.

Yes, I realised that once I realised the staff in your image was favre specific.

I'll measure mine tomorrow, at least as well as I can without taking the wheel off.

Seems I've reached the stage where I actually NEED a staking set rather than just wanting one. I've watched 2 sets of tools for replacing rubbed in jewels sell on eBay over the last week too.

I'm at least now feeling a little more confident that this is repairable, maybe even by me

Thanks.

[nevenbekriev]

You first need to see this video.

The stone You need is with specific shape and is identified with 3 sizes. The type is 'balance hole stone', the specific here is that hole walls are not cylinder, but have rather olive shape, or toroidal actually.  One of sizes is the hole diam, the other is the outside diam and third is the height. The idea is the stone to get in the 'nest' in the plate when it is opened and  the upper surface of the stone to be at some small distance from the end stone.

[graemeW]

1 hour ago, nevenbekriev said:

You first need to see this video.

The stone You need is with specific shape and is identified with 3 sizes. The type is 'balance hole stone', the specific here is that hole walls are not cylinder, but have rather olive shape, or toroidal actually.  One of sizes is the hole diam, the other is the outside diam and third is the height. The idea is the stone to get in the 'nest' in the plate when it is opened and  the upper surface of the stone to be at some small distance from the end stone.

Thanks, that looks easy enough

[graemeW]

A little hard to tell until the jewel is out, but I believe it's going to be about 1mm. I have measured the pivots and they are saying 0.07mm. The lower pivot the callers are flicking between 0.07 and 0.08.

I know digital callers aren't the best thing to use. I do have some micrometers, but for now, let's just assume the measurement is correct.

If the pivots are 0.07, would a 0.08 hole jewel be what I need?

 

16 hours ago, AndyGSi said:

If it is a Favre 13 then you should be able to check the dimensions.

Been measuring the staff, as well as I can with the wheel and roller on. I'm getting the same measurements give or take. I get 400 overall length, not 398. B was 199, not 197. J I can't measure, but 90 looks about right. G I can't measure either. K I get 58, not 60.

But, I'm using digital callipers. They are ok, repeatable, but I don't trust their calibration. I guess it's safe to assume it's the right staff as everything is very close.

[AndyGSi]

Yes everything looks OK for the staff and maybe @nevenbekriev could point you in the direction for the jewel.

[graemeW]

13 minutes ago, AndyGSi said:

Yes everything looks OK for the staff and maybe @nevenbekriev could point you in the direction for the jewel.

Poked the old jewel out. No going back now! It's not 1.00, it must be 0.90. I only got a smidge under half out in one piece, and it's daft tricky to measure. But I get maybe 0.91. 0.92 feels a bit loose, 0.90 feels a bit tight. But considering the options are 0.9 or 1.0, i guess I only have one choice. 

Just when I thought I was getting used to dealing with tiny stuff, a new challenge turns up. Tiny stuff that's also transparent!! 

The pivots I'm sure must be 0.07. Set the callers to 0.08 and the pivot passes without touching. Set them to 0.06 and the pivot won't go through.

Can't put a 0.07mm pivot in a 0.07mm hole. I presume clearance isn't calculated into the dimensions already.

I'll order a cheap roller remover. I might just make some stakes and an anvil to get this job done. I will buy a staking set, but I'm holding out for a comprehensive, complete, decent one. Don't want to order a Chinese set just to get this done if I want a better set after.

[graemeW]

Got the micrometer out as I didn't trust the callipers.

Got a measurement of 0.10 on the old pivots. Very repeatable so I trust than more. Measurements done under microscope to be sure. So 0.11 hole then I guess.

Outer diameter though measures 0.93. The only options are 0.9 or 1.0, so I guess I have to go with 0.9

[AndyGSi]

What jewels are you looking at?

[graemeW]

31 minutes ago, AndyGSi said:

What jewels are you looking at?

Seitz flat bottom olive hole on cousins

Edited February 4 by graemeW

[AndyGSi]

I was looking at the cylinder jewels forgetting it's for the balance.

[graemeW]

11 minutes ago, AndyGSi said:

I was looking at the cylinder jewels forgetting it's for the balance.

I didn't find those. The Seitz ones don't give a thickness measurement.

End float is set by the cap jewel though right? Just needs to not foul the shoulder on the pivot I assume.

They are cylindrical rather than olive. That's why I didn't find them. Am I right in thinking I need olive? It's hard to tell, but under the scope, looking at light reflection in the hole of the broken jewel, I think it's olive. Balance jewels normally are right?

I'm just picking up scraps of info here and there though.

 

[AndyGSi]

Yes balance jewels are normally olive to reduce friction.

If it wasn't rubbed in I probably have given the others a go.

Going back to the pivot hole. I presume you've got nothing to measure the existing one with?

[graemeW]

8 minutes ago, AndyGSi said:

Yes balance jewels are normally olive to reduce friction.

If it wasn't rubbed in I probably have given the others a go.

Going back to the pivot hole. I presume you've got nothing to measure the existing one with?

I haven't. The bottom jewel is smashed to bits, but the top one is fine. I thought I had some smoothing broaches, was going to see of I could get an idea of how far in it would go, then measure that. But they are all cutting broaches.

I'm pretty sure the pivots are 0.10 though. Unfortunately, I can't guarantee the new staff will have the same diameter pivots.

Maybe I should order the staff, measure it, then order the jewels. Seems like a waste paying multiple postage though.

 

The staff and jewels come to £36 all in. That's fine, if they work together, but if they don't I will be buying more jewels at £25 a go until they fit!

Stock is limited, so I need to decide and go for it.

 

[AndyGSi]

6 minutes ago, graemeW said:

I haven't. The bottom jewel is smashed to bits, but the top one is fine. I thought I had some smoothing broaches, was going to see of I could get an idea of how far in it would go, then measure that. But they are all cutting broaches.

I'm pretty sure the pivots are 0.10 though. Unfortunately, I can't guarantee the new staff will have the same diameter pivots.

Maybe I should order the staff, measure it, then order the jewels. Seems like a waste paying multiple postage though.

 

The staff and jewels come to £36 all in. That's fine, if they work together, but if they don't I will be buying more jewels at £25 a go until they fit!

Where in the world are you?

Did you spot that the oilve jewels on Cousins are limited anyway?

[graemeW]

5 minutes ago, AndyGSi said:

Where in the world are you?

Did you spot that the oilve jewels on Cousins are limited anyway?

I'm in the UK.

I spotted a few were discontinued. I don't know if their range is limited, is that wjat you mean?

They seem to have what I need though, unless I can find a flat bottom, olive hole, 0.11 x 0.93 which is my best guess at what i need.

They don't have the 0.11 x1.00 in stock, but I'm certain that won't fit anyway

[LittleWatchShop]

Very interesting thread...a little above my pay grade...

For me, if I got to wit's end trying to find the correct jewel for a vintage movement that I owned, I might consider drilling it out to open the hole to a size of a jewel that I already had.  Then insert a friction fit jewel. I wonder if any of the experts would consider this an option.

[AndyGSi]

11 minutes ago, LittleWatchShop said:

I might consider drilling it out to open the hole to a size of a jewel that I already had.  Then insert a friction fit jewel. I wonder if any of the experts would consider this an option.

This would be the best option but think I remember @graemeW
mentioning earlier that he didn't want to go down that route?.

[caseback]

Not beeing deterred by the fact that you're specifically asking "experts" (which I'm definately not!), I would say it would depend on whether or not originality is an issue and what the impact on the value is..

[Neverenoughwatches]

On 2/3/2025 at 7:50 AM, graemeW said:

Thanks, that looks easy enough

Lol, it's not...Nev just makes it look that way

[graemeW]

Originality and value are not big concerns.

Being able to successfully complete the repair is the main concern.

I've just thought though. Are the outer edges of the jewels different? The thickness will be different too won't it?

Will the new jewel even fit?

1 minute ago, Neverenoughwatches said:

Lol, it's not...Nev just makes it look that way

Yeah, maybe achievable was the better word

[Neverenoughwatches]

9 minutes ago, graemeW said:

Originality and value are not big concerns.

Being able to successfully complete the repair is the main concern.

I've just thought though. Are the outer edges of the jewels different? The thickness will be different too won't it?

Will the new jewel even fit?

Yeah, maybe achievable was the better word

Absolutely Graeme , everything is achievable given time, and that depends almost entirely on skill and knowledge...which Nev has a metric tonne of...which is why he makes it look easy. I do have a question G... how did you remove the old jewel ? I think you said you popped it out.