An 1.25" insert endmill is a large tool. You need quite a bit of power to run it, and quite good clamping on the part to resist the forces.
How long is this crank? Somehow I'm having trouble imagining something with journals over 1.25" wide and a throw of only what.....3/4"?
If you can post a picture of the model, it might give us a better idea of where the tool has to fit, and so on.
Do you have a 4th axis to hold the part? I would find it a daunting task to do much milling of the throws with a manually operated dividing head. I mean you could but it would be about as much fun as milling a circle face up on the table, while cranking X and Y by hand
First you get good, then you get fast. Then grouchiness sets in.
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)