- Mar 16, 2022
Can anyone tell me the proper part # or even better where I might find that type of information as well as maybe where to get one?
Thanks for that! I'll order a medium anyways and keep looking for the other. First thing I did was ask Dave. Normally I just email him and ask for a part and if he has it he sends it. The reason I had to ask which spring was right was cause he didn't have one. LOL! I'm still new so I haven't found a lot of resources to find what original part numbers are.I wouldn't be afraid of using the 2205 of the medium thickness in a 15J watch. Like I said, the Dennison 2 1/2, or .215mm may not be easy to find. You might contact Daveswatchparts to see what he has. Maybe he'll have the thinner one? Good luck.
I actually DO have an electronic copy of the Chicago Course! I'm using it to learn as much as I can and so far it been fantastic. I didn't see any charts or anything in the mainspring lesson but theres a ton more files to look through! thanks for the other places mentioned as well I'll look at the PWDB and see how I missed it!If you ever buy, borrow, or steal a copy of the Chicago School of Watchmaking courses, you'll find some useful tables relating to mainsprings for American pocket watches.
Pocketwatchdatabase.com has a few different Waltham parts catalogs uploaded there. There is a 1909 Waltham materials catalog that would give you the MS numbers (Pg 25) for watches made prior to that year.
I see that PWDB has the 1940 catalog. It has the MS page as well.