Help with Fusion CAM for CNC

[The Bitter End]

Good morning Everyone 

I recently got myself a desktop CNC in the hope of expanding my skill set in general, as well as perhaps creating certain parts for my current and future models. I am reasonably tech savvy and I have found Fusion to be fairly user friendly and I am enjoying the process of learning how to use the software. I have however hit one major hurdle and I was hoping that one of you ginfted individuals could help. 

I created this model for hatch coaming....(the grating running in the opposite direction will be slotted in later, this approach was taken from @mtbediz)

 

My issue is that instead of a logical toolpath which simply runs up and down the X and Y axis to create these slots, cat creates the most absurd tool paths, which have also resulted in 4 broken end mills. 

 

Any advice on how to improve this, or even a suggestion on a course or resource to improve my skills, would be hugely appreciated, I have spent hours battling with this issue without any success. 

I am a complete newby so I'm hoping the solution is a simple one which I have just overlooked.

 

Cheers

 

Haiko