Advice on Carbon to Alloy Mainspring Replacement

[Neverenoughwatches]

1 hour ago, rehajm said:

I don’t know what it’s worth but I know what I paid . Thanks- it may have to wait a while- my parts trays are full at the moment…

I suggest you pop in an ebay search. If it runs or you can get it running then from your comment i think you may have scored a win .

[rehajm]

5 hours ago, Neverenoughwatches said:

I suggest you pop in an ebay search. If it runs or you can get it running then from your comment i think you may have scored a win .

I see what you mean. Yes the  tg says it is a good runner keeping very good time. Does ‘Even a blind squirrel can find a nut’ need UK translation? Where’s Susie Dent when you need her?…

I will report there were some stunning bargains the day I won this lot. I watched two Pepsi Rolex come up in a smaller London house - one sold for a single bid at less than half the going rate, the other went unbid. Out of my league but would have covered my horology expenses for a long time…

Tip: It was Thanksgiving in the US and likely there were no Americans to bid…

Edited December 10, 2022 by rehajm

[rehajm]

On 12/6/2022 at 10:57 AM, nickelsilver said:

The Generale Ressorts book shows a 13"' (ligne) Smiths movement, which this one is, as using a spring 1.60 x 0.135 x 660 in a ring 14.5mm diameter. 0.17 seems really thick for a 13"' movement, but it is a pin lever (and not a very tall spring), and GR does have some errors in the book. It's not uncommon to find springs far off the original size that have been used in the past to get the watch going, which might explain the height difference.

 

For a spring that should work according to your measurements Cousins has GR ref 3398 1.30 x 0.17 x 520 x15, which should be fine (and cheap at 7 pounds).

 

 

An update for anyone following...the GR recommended 4585 1.6 height looked lovely in the barrel but did not allow the barrel cover to close...fortunately I purchased both and the 3398 referenced spring, while looking a bit wrong sized in barrel, at least allows for the barel to be closed...

[Jon]

On 12/9/2022 at 7:55 AM, Neverenoughwatches said:

Oooooo please can i have at the military, a W10 ? Just had a look Alnwick, a bit far from me but next time I'm up in Newcastle I will drop in.

Absolutely Jon , that would be great and appreciated by all members. Thank you.

I've put that mainspring calculator in my cloud storage, so feel free to download it.

https://docs.google.com/spreadsheets/d/17noK3_STuT7pQCAqFjIpUyZ4XweRyGdK/edit?usp=sharing&ouid=117325986396951414363&rtpof=true&sd=true

Enjoy!