Mainspring replacement.

[George12]

Help!  
New today, just dismantled a pocket watch!  
Mainspring bust, so looking for some info to replace it.

Cousins list one that seems correct size, ie 1.8 mm high, 0.18 mm thick,  450 mm long and 15 mm barrel.    GR 5381.

But they don’t appear to state if there’s a hole for the arbor.

 

Grateful for any more information. Thanks.

[Nucejoe]

Welcome to the forum.

[watchweasol]

Hello and welcome to the forum,  The issue with mainsprings is usually the fitting of the anchor point in the barrel wall as there are many types, the fitting onto the center arbour is normally a hole where the hook attaches to.  see attached picture.