The Workshop 

View the New Database in progress:New SN Database

To add your serial number to the SBL Workshop Database, e-mail your information to:wswells@earthlink.net

To purchase a Pdf copy of your Serial Number Information from South Bend Lathe Co.,:Serial Number Card

South Bend Lathe serial numbers are stamped on the front tailstock end of the bed, between the flat and V-ways.

Records show that lathes were first numbered sequentially, beginning approximately, with number 700, in July 1910.

In March of 1947, a new serial number system was introduced which added a three-letter code and a model/series revision number,
to indicate the swing, the gear and apron combination, type of motor drive, spindle hole size, type of swing, and if any special features were added.

The post 1947 numbering systems are recorded by the size letter of lathe, each one having its own sequential numbers.
For example, after the old system was ending at approximately serial number 186500,
The 9-inch Workshop (N) sequential numbers started at 1N, 2N, 3N and forward.
The Light 10-inch (10K)(K) introduced in late 1949 and based on the Workshop series starts at 1K, 2K, 3K and forward.
The larger letter series lathes also followed the same numbering system.
10-inch (Heavy 10) (R) includes 10L and 10R, large spindle hole and regular spindle hole lathes. 13-inch(T), 14-1/2(F) and 16-inch(H)

Below is a table that shows the relationship of the trailing letters for the Post 1947 Series S lathes: N, K, R, T, F, H.
Only the first letter identifies the size of lathe:(N-K-R-T-F-H), 9, 10-light, 10-Heavy, 13, 14-1/2, and 16.

Keep in mind that when searching the database, try to determine if your lathe is pre or post 1947.
The pre 1947 lathes are listed sequentially, and the post 1947 lathes are listed by size letter/lathe size.
All older Series O, N, R and T are not size specific