where to get watch jewel for replacement

[east3rn]

Hello. 

I am working on this  vintage A.Schild movement and a jewel on the wheel bridge.

It is a jewel for the 3rd wheel but is cracked so needs replacement.

I measured the outer and inner diameter and they are 1.2mm and 0.17mm respectively.

Could any one help me find the replacement for this jewel??

I am always grateful for your help.

[saswatch88]

first you need to know the shape of the jewel i believe its most likely convex olive shaped. inside shape doesnt mean much so go with olive shaped holes not cylindrical. top shape can be seen with naked eye. its either domed up in (convex) or domed in (flat). you will have to measure the width of the jewel and the pivot with a pivot gauge. pivot gauges are hard to come by...sometimes if you search mainspring gauge on ebay you find one since they look similar to mainspring gauges because they have a slit that you slide the pivot in until it stops. others are jeweled gauges but they are kind of expensive. i attached a sample of both from ebay and the seitz jewels ordering page from ofrei.com. you will see the diagram of jewel shapes.

https://www.ebay.com/itm/Watchmakers-pivot-gauge-jewelling-tool-jacot-tool-Watchmakers-Clearance/323769671356?hash=item4b622d1ebc:g:iSoAAOSwLdVcoPJo&frcectupt=true

https://www.ebay.com/itm/KWM-Zapfenmass-Pivot-Gauge-Clockmakers-Clock-Bushing-Size-Guide-Watchmaker/113713126411?hash=item1a79d49c0b:g:djQAAOSw8bdcrK7c&frcectupt=true

http://www.ofrei.com/page939.html

[east3rn]

  On 4/10/2019 at 1:20 AM, saswatch88 said:

first you need to know the shape of the jewel i believe its most likely convex olive shaped. inside shape doesnt mean much so go with olive shaped holes not cylindrical. top shape can be seen with naked eye. its either domed up in (convex) or domed in (flat). you will have to measure the width of the jewel and the pivot with a pivot gauge. pivot gauges are hard to come by...sometimes if you search mainspring gauge on ebay you find one since they look similar to mainspring gauges because they have a slit that you slide the pivot in until it stops. others are jeweled gauges but they are kind of expensive. i attached a sample of both from ebay and the seitz jewels ordering page from ofrei.com. you will see the diagram of jewel shapes.

https://www.ebay.com/itm/Watchmakers-pivot-gauge-jewelling-tool-jacot-tool-Watchmakers-Clearance/323769671356?hash=item4b622d1ebc:g:iSoAAOSwLdVcoPJo&frcectupt=true

https://www.ebay.com/itm/KWM-Zapfenmass-Pivot-Gauge-Clockmakers-Clock-Bushing-Size-Guide-Watchmaker/113713126411?hash=item1a79d49c0b:g:djQAAOSw8bdcrK7c&frcectupt=true

http://www.ofrei.com/page939.html

Expand  

Wow thank you again for your advice!!

I was struggling to find where to get the jewels and there it is

Actually I have two more things that I am not sure of.

1) I measured the outer diameter of the jewel with the jewel inserted in the bridge.

Is it OK to do so??
 

2) I measured the diameter of the pivot of the 3rd wheel which goes through the jewel and it was 0.16mm.

Does that mean that the inner diameter of the jewel is same as well??

Thank you!!

 

 

[yankeedog]

A more practical approach might be to replace the bridge.provided one could be found.

[saswatch88]

  On 4/10/2019 at 12:01 PM, east3rn said:

Wow thank you again for your advice!!

I was struggling to find where to get the jewels and there it is

Actually I have two more things that I am not sure of.

1) I measured the outer diameter of the jewel with the jewel inserted in the bridge.

Is it OK to do so??
 

2) I measured the diameter of the pivot of the 3rd wheel which goes through the jewel and it was 0.16mm.

Does that mean that the inner diameter of the jewel is same as well??

Thank you!!

 

 

Expand  

no you have to remove the jewel first before you measure its diameter accurately. and yes diameter of the pivot  would be the diameter of the hole in the jewel.

[praezis]

  On 4/10/2019 at 3:39 PM, saswatch88 said:

 and yes diameter of the pivot  would be the diameter of the hole in the jewel.

Expand  

No of course.

In that range add 0.01 mm to the pivot diameter and you get the hole diameter.

Frank