I tried to find the difference between the Kenmore cams. I found
https://www.pinterest.com/pin/467248530072277768/ that shows the different ones. I could not find where it came from. It appears that there are major differences between C & E. The E has a larger diameter center. The difference between the flat Singer cams would be the notch and holes for the pegs that would fit on the 'cam holder.'
Janey - Neat people never make the exciting discoveries I do.
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