If anyone recently ordered 12S Illinois Mainsprings (Bestfit # MS-JA423 or S LaRose #039338-045A) you might want to double check them. They are supposed to be 11x6x18 1/2. Even though my packaging was labled accordingly, the mainsprings I received were actually 18x5x21 1/2.

Better to find this out during idle-time rather than when I did... in a time sensative situation.

Mike Miller

Mike,

Couldn't agree with you more! I ordered two 37s size mainsprings from S. LaRose and stored them away for over a year. When I got ready to use them, the inner hole for the arbor was incorrectly punched. The spring was so stiff; I couldn't open the coil up enough to file off the excess area.

Mainspring Slipping

John D. Duvall
IHC Happy Camper 192
IHC185 Watch Repair Moderator