I agree with JBoogie about the welded construction on the frame. More specifically, the welded construction is on the end bell. The bearing housing also looks too modern for an old motor. A motor of that age would have had a cast iron end bell, and the bearing housing would have had either grease plugs (if ball bearings used), or a means of oiling the bearing (if plain bearings used). The bearing housing and end bell look shop-made rather than factory made. The other big question is why an electric motor would be built with the windings out in the open as this one has. Most motor designs try to protect the windings and moving parts from dirt, foreign object damage, and to keep curious fingers out of the works.
The stator is cast iron, which would be in keeping with an old electric motor. My guess is one of several possibilities:
1. The motor was modified for use as a teaching aid in a trade school or technical school, making the windings readily visible and accessable.
2. The motor was built original with cast iron end bells. Possibly, during WWII, when material shortages were the rule and new electric motors were going to
defense-related work, this motor had a broken end bell. Rather than scrap it, particularly if a new motor was not readily available, the fabricated steel
end bell was made by either the owner or a local shop.
The amount of work required to fabricate that end bell is considerably more than the work associated with a cast iron end bell. It is an interesting motor, but, like JBoogie, I have my doubts as to whether it is a genuine antique. The open end bell with visible windings is nice to look at, but in the real world, none too practical. Short of an electrical lab classroom, I could not see any reason that an open frame motor would be made. Motors rely on cooling fans or blower vanes on the rotor shaft, and ample cooling slots in the end bells or stator. These reduce the amount of dirt and foreign objects getting into the windings and keep rodents from chewing on things. No cooling fan visible on the end of the rotor shown in the photos, windings out in the open, all adds up to a motor likely modified for an electrical lab or similar teaching setting.
