One Way Of Solving The Parts Problem

[WillFly]

My 1939 Unitas 173 has both a broken mainspring and a broken barrel arbour. A replacement spring is no bother - Cousins do one for just over £7, but the arbour's a different problem as parts like that are not easy to source. By chance I spotted an identical 173 head on eBay - movement in good condition - and managed to get it.

 

Rather than swap the bits over, I'll probably put the whole replacement movement into the existing case and use the existing dial and hands - which are in much better nick than the replacement dial and hands. All subject to testing when it arrives, of course.

 

The question is: what to do with the original, faulty movement? I could recoup some cash by selling as spares or repair - these movements are quite rare, and I've seen a complete watch like mine, in good condition, selling in a shop for nearly £300 - so I'd certainly get something back. However, given the increasing rarity of movements like this, it might be better to keep it as "spares or repair" for myself...

 

The following pics are (1) my original movement (2) the replacement.

 

Edited September 28, 2014 by WillFly

[Vich]

Had to smile when you mentioned selling the watch.  You have a reputation, probably undeserved and made up ?, for hanging onto and acquiring stuff.  in this case, however, I would be hanging on, bide time something will turn up and you could end up with two desirable items - we will see then whether you can sell :cool: .

 

Is the balance spring on your replacement ok, its probably just my eyes (can't find any of the multitude of reading specs I have just now) but the coils look really close as it gets towards the cock (am I allowed to say that ?).

 

Cheers, Vic

[clockboy]

The answer is to make another arbour or modify an existing arbour.  Having said this I must admit my skills using my watchmakers lathe are still limited but are improving. I have spent many an hour trying to make a balance staff and failing at the very last moment but I never give up. The hardiest part of making an arbour would be is how to create the notch that grabs the spring. 

Edited September 28, 2014 by clockboy

[WillFly]

The hairspring on the replacement does look unevenly coiled from the photo, whereas my original is very good indeed. There may have to be a cannibalisation of one or other of the movements in order to get one perfect whole.

 

I actually sell quite a lot of watches! I've just sold three pocket watches and am in the process of selling a fourth on eBay - a 1943 Waltham US military watch with Ordnance registration code engraved on the back. And, periodically, I unload a whole clump of wristwatches that haven't grabbed my attention over a period of time.

 

Like all collectors, one's interests change over time - some areas get narrower and new ones appear.

[Vich]

As I suspected Will. I also have been unfairly treated, I was told I was starting to drink too much and getting lazy ! where both of these facts have always been constant and unchanged over the years - you would think my beloved would have known that ! :D

[Daniel]

I seen a video on you tube where a guy fix a main spring barrel . but cant get the link to paste in the chat box here :(

[bobm12]

Absolutely, it involves de-tempering the end of the spring and then bend it or modify it as needed and then tempering it again....I think I saw it too. It was a good video.

[Andyclient]

Just done a new balance on a Unitas 173 today Will , Cousins still listed the balance fortunately.

Is there nothing you can do with the arbour ? is it the screw sheared off ?

Will an arbour from anything else fit ?

p.s no i didn't relume the hands , just realised how bad they look in Macro lol

 

Edited September 30, 2014 by Andyclient

[WillFly]

Yes - the screw has split and sheared as well. The replacement movement is on its way - I'll see what can be done when it gets here.

[bobm12]

Isn't the hour hand upside down? Or maybe it is me...

[Andyclient]

Isn't the hour hand upside down? Or maybe it is me...

Don't think it is , thats why i mentioned about the bad luming , the pointer is pointing down so i think it's the right way up, it's just a over zealous lume job i think, will have to sort it now i've noticed lol

[daz]

I would hold on to it Will as you never know you may one day need the parts to repair the movement you have, I sold a spare movement I had for Bulova Delegate Cal 10BM as I thought I would not need it as mine was good.This was a mistake which saw me having to purchase another spare movement when mine developed problems...