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Repairing A Worn Barrel Bridge

clockboy

By clockboy
in Watch Repairs Help & Advice

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clockboy Distinguished Member

clockboy

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I was asked to look at a Sekonda that was running for approx. 8/9 hours & then stopping but would run with again with encouragement. When I opened the watch it was extremely dirty But I noticed that under the mainspring barrel there was wear on the plate. After reassembling the barrel & bridge it was apparent that the barrel bridge hole for the barrel was very badly worn. The answer was to re-bush the hole.

post-234-0-35082100-1444034542_thumb.jpg

 

I had some clock bushes & luckily had a bushing that had the correct size hole. The problem was however the plate was only 0.373mm thick so effectively I had to make a bushing that was not much more than a washer.

 

I turned the bush down on my lathe to a reasonable working thickness & then reamed out the hole for the new bushing (3.00mm).

post-234-0-83542500-1444034757_thumb.jpg

 

Then I fitted the bushing using my staking set & tested the hole was correct. After a lot of broaching using a smoothing broach achieved a good fit.

post-234-0-89286300-1444034906_thumb.jpg

 

I then removed the new bushing & using a soft piece of wood as a base filled & burnished the bush to the correct thickness.

post-234-0-61027400-1444035002_thumb.jpg

 

Then I finally pushed the new bushing in with my staking tool but added for safety some lock tight to it,s edge as it is a very thin bushing. Job done just the watch to re-assemble.

 

post-234-0-98294900-1444035082_thumb.jpg

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clockboy Distinguished Member

clockboy

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  On 10/5/2015 at 11:13 AM, oldhippy said:

A very nice bit of work.

 

Question, Aren't parts available any more for this cal.

Probably but I thought learning how to do this repair useful for watches without readily available spares.

oldhippy Distinguished Member

oldhippy

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Posted
  On 10/5/2015 at 12:40 PM, clockboy said:

Probably but I thought learning how to do this repair useful for watches without readily available spares.

A good point.

GuiBer WRT Addict

GuiBer

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Posted (edited)

Great work clockboy, and also very didactic. Thanks!

 

( Just a question: would it not be possible to push in the new  bushing with the Seitz tool? )

Edited by GuiBer
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