Hi @jordan3PPHR – that's an interesting router setup! Or at least not one I've heard of before. Out of curiosity, what kind of router do you have / would you say you consider dual spindle routers to be common?
There's not a way to define a spindle for a tool currently, at least not in the way I think you are looking for. What you can define is a turret, and I'm guessing you could do some post editing to have your milling post consume that parameter and get things to work the way you like. I am not a post expert so I'm not totally sure what is and isn't possible, but I know folks have been able to achieve some pretty creative stuff in the past.
Another option, if you don't want to edit your posts, is to use Manual NC. There are many options, including "Pass Throughs" which can write code directly into your program. This way you can write whichever code or codes you need to call the specific spindle before the "tool change" in your program (or do whatever else needs to happen). Is this what you were looking for, or do you need to be able to do something else?
As for the toolpath screenshots, it looks like the top one is Adaptive Clearing, which uses a constant engagement angle as part of the algorithm. That's why you get those odd curves as the toolpath output. If you want a toolpath that will follow the edges like what's on the bottom, 2D Pocket or 2D Contour should both do the trick.
Marti Deans
Product Manager, Fusion 360 Manufacturing
