So far, I have to take the watch apart, measure the old staff. Then look at the Balance staff dimentions for American pocket watch.doc cross referencing the Illinois parts guide thats on IHC185 for Illinois watches to find what the staff number is. The others (Hampden, Elgin, Hamilton) its just the Balance staff dimentions for American pocket watch.doc. Is there an easier way to do this? Are there any books that give part numbers for a specific model?

Jim, a good book to have for all kinds of part numbers is, Illustrated Manual of American Watch Movements, by the E. & J. Swigart Co.

Thanks Brian, it looks like I am in luck because its been reprinted.

Jim,

What you should do is remove the upper and lower hole jewels and measure them and choose your staff based on that size. You have to take them out anyway to clean and oil them. We are working with watches that may be well over a hundred years old and who knows what has been done in that time. You might find that the upper and lower hole jewels are different sizes! I have found that more than once.

Thanks Roger
I agree Roger, sorry if I didnt mention that in my earlier posts. Its always best to take a watch apart before ordering and make sure the staff (and jewels) are the correct one regardless of what a book may say. As you say, who knows whats been done in the last hundred years. I am just a little frustrated picking out the correct staff out of a list of possibilities. If there is a book that can help limit the possibilities down a little, its worth it to me to get it. I will still check the dimensions.

Just got the book, I can see that this one is going to be helpful in more ways than just the balance staff.