When were the spindles with the full race behind the bearing changed to the straight sides?
I believe you are asking when did the shoulder on the spindles change from basically round to having a flattened area on both sides to make it easier to remove the bearing race. At the 2005 posting at: http://www.mtfca.com/discus/messages/29/34124.html Ken Kopsky posted the photo below. He indicated approximately 1919ish for the change. On the left the round shoulder, in the middle the flattened shoulder, and on the far right the flattened shoulder on the 1926-27 spindle that helped lower the “Improved cars.” That photo was also posted recently if I recall correctly.
On page 26 of “Model T Ford Parts Identification Guide vol 1” Gail Rodda shares the change occurred 1917 or 1918. When the previously round shoulders were now made with flats to make it easier to remove the bearing race.
And I looked but I did not see that feature listed in the MTFIC Judging Guidelines 6th edition. Does anyone have any information from the “change cards” or “factory drawings” that might help narrow down that time frame some?
Hap l9l5 cut off
I think I said "Pre 1919" ish. But I would trust Gail.
And here I thought I was going to learn about some recently found speedster accessory !
Is this what you wanted to see?