The Singer Class 66 Sewing Machine models feature a low shank and an oscillating hook. They use Class 66 bobbins and 15x1 needles.
Cabinets for Class 66 Machines
A 66 Treadle
The 66 Bobbin Case and Hook Assembly
Threading Diagram for Model 66-1
Notice that the presser foot attaches onto the back of the presser bar. This characteristic is exclusive toModel 66-1
(Picture Courtesy of Dorothy Brumleve)
This picture shows the "thistle" decal.
This picture shows the "red-eye" or "red-head" decals.
(Picture Courtesy of Charles Law)
(Oiling Diagrams Courtesy of Dorothy Brumleve)
Following Compliments of Sharon Reese:
This Singer 66 was made in the 1920's and started out life as a treadle. Later, a Singer dealer added a motor and a numbered tension dial. The decal type is called "red eye" by collectors (There is also some green in the decals). I'm not sure of the exact age of this machine because the serial number was hard to decipher.