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Elgin 448 Cap stone removal


mikecj

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All,

I am working on an Elgin 448 watch. It is almost 90 years old and had a lot of crud on it. I'm working on the balance  trying to remove the cap stone (jewel) in order to clean it. I managed to remove the two small screws (locations in red) that hold it in place without to much trouble. However I cannot remove the jewel because of the brass inserts surrounding it (locations in yellow). 

I thought about applying heat or cold but am worried about damaging the hairspring.

Any suggestions? Attached is a picture of the unit.

Thanks, 

MikeCJ

IMG_20220120_130341890_LI.jpg

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The cap jewel is mounted in the brass insert, you do not remove it !

First remove the balance + hairspring - v carefully !

Take out the two screws, then turn the cock over, and push the jewels out from below. 

You will then have the hole jewel, in a brass surround, and the cap jewel, also in a brass mounting.

I have an old Elgin 455 which I've just pushed the (very dirty) jewels out to show you -

0001.thumb.jpg.455f9f064ffda4a8f92c1043b93d298c.jpg

0002.thumb.jpg.06daf13d7eb498a4dcf4cee4d32cb549.jpg

 

Edited by mikepilk
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21 minutes ago, mikecj said:

I thought about applying heat or cold but am worried about damaging the hairspring.

If you had a blowtorch you should Be able to melt the brass and get the jewels free. Unless of course you're trying to service the watch then this would be a really bad idea.

I'm assuming this is your first pocket watch?

What you want to do is loosen the stud screw push the stud out a little bit not too far so it's loose remove the balance bridge remove the balance wheel Keeping the hairspring on the balance wheel of course. Because if you going to clean the watch you have to take the balance wheel out anyway.

To understand the jewels I have a picture. The jewels are burnished into brass settings. This is why blowtorch would be a bad idea because you want to keep them in the settings.

Then because I was too slow to answer somebody beat me to the answer with nice pictures I think you get an idea of how it all goes together or comes apart

jewels American pocket watch balance in settings.JPG

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Mike is on the money,

JohnR is kidding,( too many help and advice to give) 

Remove the balance first to get it out of harms way.

Give the cock assembly a 48 hr soak in Coca cola or a bath in ultrasonic or use penetrating oil .

The end stone is happy in the brass plate, thats where is suppose to stay, all you need is to gain access to otherside  and clean it real good.

Good luck 

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52 minutes ago, Nucejoe said:

Give the cock assembly a 48 hr soak in Coca cola or a bath in ultrasonic or use penetrating oil .

The end stone is happy in the brass plate, thats where is suppose to stay, all you need is to gain access to otherside  and clean it real good.

Traditionally on American pocket watches to clean the balance jewels they have to be pushed out. The screws have to come out but there's a problem with that? The screws at some point in time will end up getting stripped that's an issue. At one time they made oversized screws to fix the problem but you're not going to find those. The preferred way would be to just clean it with a decent ultrasonic machine but it depends on how bad the lubrication is as to whether you can clean it out or not when it's assembled.

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8 minutes ago, JohnR725 said:

Traditionally on American pocket watches to clean the balance jewels they have to be pushed out. The screws have to come out but there's a problem with that? The screws at some point in time will end up getting stripped that's an issue. At one time they made oversized screws to fix the problem but you're not going to find those. The preferred way would be to just clean it with a decent ultrasonic machine but it depends on how bad the lubrication is as to whether you can clean it out or not when it's assembled.

I didn't mean cleaning with the endstone on cock assembly. OP needs to check the other side of end stone to make sure its in good condition, suggested soaking cuz op says there is  lots of crud is on it. 

Regards 

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14 hours ago, JohnR725 said:

 The screws at some point in time will end up getting stripped that's an issue. At one time they made oversized screws to fix the problem but you're not going to find those. 

I've come across the stripped screws many times (e.g. the left screw in the above movement). I didn't realise they made oversize screws to fix the problem. I use a tiny drop of Loctite.

Edited by mikepilk
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