Vintage Windmill and Wind Generator Forum

I also picked up a June 1938 Aermotor price list that had some good info. I have encountered a handful of E & F Aermotors that had 703 1/2 hubs, early E & F 702s that had an unmarked hub with the 602 style smooth shank arms and a lot of E & F 602s that had clearly marked 503 hubs with smooth shank arms.

Here are the pages from the May 1938 catalog








So the E & F 602 had the 503 hub with the smooth shank 536 arm.
The early 1933-1938 E & F 702 had the 703 hub (not seen that had part number in casting) using the smooth shank 536 arm.
The post 1938 E & F 702 had the 703 1/2 hub with the common 702 style arm 736.

The 536 arms in both the 602 and early 702 used those interesting 314 1/2 arm crosses.
The transition of the E & F to the 703 1/2 hub seemed to occur about the same time the 723 transition hub was discontinued for 12' and smaller mills.

Ron Stauffer
Montrose CO

A followup for some that requested what these hubs looked like. Sorry for the delay as had to replace my phone and have to be in at the desktop until I can get all my account usernames and passwords transferred.

The E & F 602s (14 & 16) had screw in arms 536 having never had V spokes. Here is a pic of E602 with the smooth 536 arm. Take note of the heavy outer lip of the hub 503 and the smooth arm 536. Arm holes in the hub 503 were closed bottom and threaded clear to the top






When the 702 came along in 1933 in the E & F already having threaded arms, Aermotor 703 hub in E & F continued using the arm 536 for the next 5 years. The arm hole continued with a closed bottom, threaded to the top and heavy outer lip similar to the 503. Here is a E703 hub, with the arm 536 and the clamp arm braces 314 1/2. The hub 703 would mate to the 702 case and held the 1/8" larger shaft of the 702.






These parts were used until 1938 when the E & F 703 1/2 hub and arm 736 came along. The 703 1/2 hub had open bottom arm holes and threading stopped an 1/8" from the top to accommodate the stop on the 736 arm. Also, the heavy outer lip of the hub was discontinued for the traditional common hub that was used throughout the 1940s and 1950s.






The late 1930s was also the time when the 6 thru 12 hub 703 was changed from the heavy outer lip to the later look. The changeover parts for putting 6 thru 12 602 parts in to parts was also discontinued - namely hub 723 & bearing carrier 753 .

Ron

I could not do any more attachments on the above post.

Early 1930s heavy lip compared to the traditional of 40s & 50s.




A F703 hub





The F703 did have the part number casting but I have not seen it on any E703s.

Ron

Lots of great info, Ron!

Thanks for putting this together.