"Automatic adaptor bridle"

[clockboy]

In a recent post this attachment was added http://watchguy.co.uk/repair-heuer-autavia-buren-12/

The interesting part for me was his use of a "automatic adaptor bridle" . I don,t know where to purchase or how to make them. Anyone any ideas as this could be a life saver when the normal auto spring is not available.

[jdm]

I had read that blog entry. Stellar work by Christian, just looking at that pivot size makes me gulp, and the rest is not for less.

Sorry, can't help with locating the adapter. But if you contact Christian he may tell you, considering the kind guy he is.

[oldhippy]

Why would you want to make one when auto m/springs come with them fitted. If you do then extremely strong m/spring is needed, must be the correct height, length is more then the barrel, you know the rest because its how the slip spring works in an auto. The hardest part is the strength and height. 

[Tiktok]

If you read the comments at the bottom of link it says he took it off an another automatic  mainspring.

The problem with modern alloy mainsprings is attaching it, it is much easier to rivet or repair an older blue steel type mainspring like watchmakers used to do years ago, but most of these type including new old stock have lost there strength/shape over time and are now useless.

[clockboy]

2 hours ago, oldhippy said:

Why would you want to make one when auto m/springs come with them fitted. If you do then extremely strong m/spring is needed, must be the correct height, length is more then the barrel, you know the rest because its how the slip spring works in an auto. The hardest part is the strength and height. 

It,s when a replacement is not available. At a push you have to fit the nearest size available but this idea is another way (if it works that is)