AS 175 balance jewel

[luiazazrambo]

Hello happy Watch and Clockmakers,

My third question for this AS 175 specimen.

I am at the re-assembly stage and I realized that one of my balance jewel is broken. Never replaced one so maybe its the time to try it?

I assume I need to follow the advise from Mark: Replace Rub in Jewel

 

I got these tools from Herr Gustav Boley:

and I also got an almost complete Star jeweling tool:

I never replaced a jewel, but based on the video i will need both tools. My question is: how do I measure the jewel itself? You measure the old one if you can? What about the hole? Do you measure the pivot diameter? And lastly where do you buy the jewels? Is there some sort of a standard? Like they go up and down in diameter, thickness, hole size lets say by x/100 mm? What do I need to read?

I know loads of questions, if too many let me just know how to order a new one please.

Take care,

lui

 

[Nucejoe]

Here lists 10.5"'   for pivot. 

https://17jewels.info/movements/a/as/as-175/

Even if the broken jewel comes out in pieces you still have the hole jewel is to fit in, to measure the ID of.

 

[luiazazrambo]

Hi Nucejoe, 

I am not sure what does that mean. Knowing that the watch is 10.5''' should help me? And I never measured a jewel, should a normal caliper work?

Best regards,

lui

 

[Nucejoe]

1 hour ago, luiazazrambo said:

Hi Nucejoe, 

I am not sure what does that mean. Knowing that the watch is 10.5''' should help me? And I never measured a jewel, should a normal caliper work?

Best regards,

lui

 

Oh Sorry,  I meant even if the jewel comes out in pieces and its OD is next to impossible to measure ,  you still have the hole on the mainplate to measure its ID. Good thing about the rub in jewels is you can fit in a jewel of slightly larger OD.

 

[Nucejoe]

Yes a caliper is accurate enough. thats if the jewel comes out in one piece,  so measuring its OD is possible.

 

[luiazazrambo]

I must admit that I was too worried to start with the jewel replacement and bought a spare movement from eBay, arrived an hour ago, but unfortunately it has no balance jewel built in so now I have to go for the jewel replacement.

OD = outside diameter i figured.

Lets go step by step then. How do I know which side of the jewel do I have to  push to get it out? And once it is out i assume i need to buy a "Flat Cylindrical Jewel". Like these: flat-cylindrical-jewels-seitz

I have to push this side:

not this one:

Right?

[luiazazrambo]

Ohh dear... my smallest bit is just too big for the jewel.... The watchmaker's life is not just joy and laughter...

[luiazazrambo]

The G. Boley tool is also too big for this jewel. I have put the balance cock back in its place with the broken jewel for now, so at least the movement would be complete. 

 

[Nucejoe]

Just google for Mark's video on  HOW TO REPLACE A RUB-IN JEWEL .

Regs 

 

[luiazazrambo]

That was the first step I did. But it did not mention how to measure / select a new jewel and where to buy it. I would have hoped that a watch part supplier would be able to provide that but based on my research and the topics here on this forum I am supposed to go for a rub in jewel not a friction fitted jewel and it seems the watch part suppliers do not have that. Furthermore none of my tools seem to be small enough for the jewel I have in this watch. My best chance as far as I can see it now is to follow the videos of @szbaloghto make my own jewel: make your own jewel and there is part2 as well.

 

Edited April 7, 2021 by luiazazrambo

[luiazazrambo]

I bought 16 donor movements for £9.71 including three As 175s. As my smallest pusher in my jeweling tool was to big for the job I tried to use pegwood to push out one of the intact jewel so I could use it in my wife watch. Here is the result:

Probably it is the time to practice some lathe work and make a smaller bit for the jeweling tool. I only have an unimat though. I used pegwood by the way because I read that this is how someone got out the jewel.

[Nucejoe]

I don't think rub-in jewels can be just pushed out.

This is above my head, lets see what @JohnR725 says.

 

[JohnR725]

On 4/7/2021 at 2:12 PM, luiazazrambo said:

am supposed to go for a rub in jewel not a friction fitted jewel and it seems the watch part suppliers do not have that

simplistically this is the problem of working on a vintage watch vintage parts typically are not available anymore. Sometimes you might vilify and some in an assortment on eBay may be perhaps

On 4/25/2021 at 2:31 PM, Nucejoe said:

I don't think rub-in jewels can be just pushed out.

it's usually best if you try to open up the setting before pushing. Pushing does work but if the setting isn't open you may very likely break the setting. Then sometimes the best way to open up the setting is to smash the jewel then you can safely open up the setting.

On 4/3/2021 at 5:14 AM, luiazazrambo said:

Lets go step by step then. How do I know which side of the jewel do I have to  push to get it out? And once it is out i assume i need to buy a "Flat Cylindrical Jewel".

first step would be to do research to grasp what the heck you're trying to do otherwise is going to end up in disaster.

Normally for burnished in jewels and I'm the start at the beginning there would be a special tool set to attempt to open up the burnished setting. Personally smashing the jewel out is the best way to go then you can open up the setting.

Then we have problems lots of problems with this discussion?

Like for instance that flat jewel is not the correct jewel that we normally would find in a balance bridge. Inexpensive watches did not use the proper jewels. So that's a plate jewel not a balance jewel that's currently in your watch. So do we want to put a balance jewel in even though it didn't originally have one or do we want to put a plate jewel in?

Then a sizable part of the world would frown on this suggestion but providing there's enough room and I can't really tell from the picture may be not perhaps I would ream out the whole and just friction in a modern jewel. It's under the cover with the end stone nobody's going to see. If you really obsessed with a burnished in jewel in need to get one that requires a time machine or have somebody make one for you or I guess you could make your own. Or if you really really had to do this you can modify a modern jewel.

just so are all on the same page I'm attaching some images you can see the difference between a modern balance jewel and atypical plate jewel. Although there is a plate jewel style with an olive hole which would probably be closer to what you have. We just have to modify it if you wanted to fit properly.

then another picture showing the difference between burnished and friction jewels. Burnished tools have rounded edges this is so you can burnish the metal over that edge. The same procedure is used to burnish stones and rings etc. so it has to have a rounded edge for the metal to go. Modern jewels have reasonably square edges because you just make a nice round hole and push them in. If you attempt to use a modern jewel in a burnished setting its problematic because you may not delegate the metal over the square shoulder. Or you got careless and tried to push the jewel out and broke the setting.

There is a way to modify the edge of the modern jewel so you can burnish it in. But I would prefer just to use the dueling set make a whole and friction and something and be done with it especially because no one is going to see it and it's going be much better to have a real balance jewel then whatever they had there in the first place because are being really cheap. The only problem as burnished in jewel setting us the burnishing apart can take up a lot of room so by the time you open up a whole big enough to have a nice smooth side it may just run out of space because you have those screws there for the the end stone. Worst-case is you would have to make a brass bushing and friction that in the first if you opened up the whole to bag and then put your modern jewel into the.

 

 

 

 

[luiazazrambo]

Sorry for the late reaction, was busy with work and family and other ongoing projects, also my covid vaccine took me down for a couple of days. I like the idea to fit a modern jewel, however I have not done that either. I mean never ever. I want to make this watch work again and ideally learn something while I fix it. Learning is just as important as fixing it. I am going to re-read the advises above and probably do further research as how to select a modern jewel how to ream out the while for it etc. Thank you.