/diy/ - Do It Yourself

For coin dies.
Can anyone foresee any mechanical issues or considerations I will have to make when building one of these from scratch?
I will post my basic designs. I will try a concept out of wood.
What kind of milling bits should I use? should I do a rough pass first with a wider cutter? will that need to be set to make a slightly shallower cut than the final pass with a finer cutter?