Skimming The Inside Of The Barrel

[clockboy]

I have been working on a Seiko auto and when stripped down I noticed that the inside of the lid of the barrel was badley scored and it looked like the spring have been dragging on the scores. Normally a new barrel & spring would be the answer but the barrel is now an obsolete item. So as a fix I attached it to a stepped chuck on my lathe and skimmed a small amount away and polished the score away. My question is this an acceptable practice because this was the only way around I could think of. I reassembled and all seems to working fine so I guess I did right 

 

I wish I had took pics to explain better.

 

P.S Whilst doing some research I found this on the net re-watch spring & barrels explained 

 

Automatic and manual winding .pdf

Edited December 24, 2014 by clockboy

[Geo]

I would have been a bit wary about sKimming the lid, a good plush would probably have done the trick. The lid has to snap inside the barrel and you don't want it to be too slack.

[clockboy]

Geo,

The seiko top is not flush its shaped on like a lid & snaps on over the main body of the barrel.

[Blacklab]

What movement is it?

[canthus]

Quite often the barrel/arbour is used in many movements. I had same problem with a 6319B and eventually got back to the base caliber and managed to source. Have you tried stefan on ebay he specialises in Seiko.

[clockboy]

Seiko 7005a if you see a drawing of this movement you will see what I mean. How I wish I had taken pics

[Blacklab]

Clockboy, I have a complete barrel out of a 7009a which is the same part, not to sure of the internal condition but looks good from the outside. If you want it pm me your address details and I will send it on next week.

[clockboy]

Thanks WRT the watch is running fine looking at it now as I type so I think the skim has worked. Geo is getting the wrong idea I think of what I did. I skimmed & polished the inside of not the barrel wall or any thing on the main barrel that holds the spring just the top which fits on with a lip effect the same as the 7009a. I always thought there was a small gap between the lid of a mainspring barrel and the spring but this looks as though it had been rubbing on the lid hence the scoring. 

However this watch is also not of any real importance so I can if time strip again and show my repair but of course I cannot show how it was before.

In the clock world cleaning up barrels with lathes is common but of cause the tolerances are not as critical as a watch 

 

Thanks very much WRT for your offer very much appreciated.

[Mark]

These barrel lids are like the Valjoux 7750 if I remember rightly.

 

I am pretty sure you have removed a couple of microns of material and I am sure it will not make much difference to the running of the watch and would actually be more benefit then impedance. Some purists will turn their noses up at what you did, but I am not one of them. I commend you for your innovation.

[clockboy]

Well it was this or scrap it. My son assists sometimes with house clearances and a few weeks ago during the clearance a box of old watches was found, 98% basic crap but this Seiko and a nice looking Casio . Also at the bottom of the box was a Bergeon quartz pusher set have not got a clue what they are used for and will give the net a search when the festive time has gone. As I have said the Seiko was a freebee and If it runs Ok I will put it on fleebay and make some beer money.

[clockboy]

Update on the Seiko,

For those who followed this post I skimmed a macro amount of steel of the inside of the lid of the barrel because of damage & a replacement was not available.

Well it has been on my wrist for the last two days and it has lost 1 minute so initially I would say the work around has worked BUT….

When on the timing machine see pic all looks good until moved to another position and there is a flurry of snow for a while before it settles down again. I don,t if is the low amplitude, a mainspring issue or something else in the watch not being correct. This is where the more experienced watch repairers knowledge comes in to play.

However because of the above I will just keep this one in my Seiko spares box. I thought it was a well worth experiment anyway.

 

 

 

[Geo]

there is a flurry of snow for a while before it settles down again.

It's winter! :-)

Great that it's working though.

[clockboy]

As I type this it is still on my wrist and is running great. You would certainly not know it has a fault 

[Geo]

I have a couple of watches in my collection with the same sort of symptom, looks bad on the Timegrapher and keep good time.

It would be interesting to hear what the professionals think about this.