Hi Rodney-
I haven't taken the latch tab on the knob apart, so it's in the same position as it was when I got the machine.
Looking at the pictures of the spring, you can see how the slope of the latch tab tends to force it outward. It is shown extended to the maximum, actually past where it would be if it fully engaged the slot. The latch works properly, applying spring pressure unless moved to the stable "off" position.
In the second picture of the first post, the latch is as engaged as it can be. Not enough. Rotating the wheel, the latch tab catches a bit on the inside of the slot, but lacking a positive hold. Turning the handwheel causes it to come loose. It will turn once around again. You can hear the tab riding on the inner surface of the handwheel flange as it seeks the slot. It will catch and come loose again and again. One couldn't run the machine this way. I can't even turn the machine by hand until I get the latch to engage reliably.
The best documentation we have is from a Franklin manual, circa 1926. The old illustrations are wonderful. The Franklin machine portrayed is like the White Rotary 11. While it's a drawing, it is very detailed and clearly shows the latch tab fully in the slot. It also seems to makes sense to positively lock the shaft knob to the handwheel, given that this is not a slip clutch design.
(Reprint from 1926 Franklin Manual)
[ATTACH=CONFIG]528349[/ATTACH]
I'm thinking of using the hand file again. If the slot was a tiny bit bigger this would work as I believe it's supposed to.
Before I do this, what's your opinion?
John