Hi Logan,
It seems that you have run into a performance problem in Fusion. We think that this is most like the root cause of the problems that you are seeing. We think that what you are seeing is just very slow compute, and if you waited a very long time, Fusion would eventually come back with the result. We will get to work on fixing this problem. The problem is in the pattern feature for the grill:

That pattern can take up to 15 minutes to compute. Again, we realize that this is not acceptable, and will fix it.
In the meantime, there are a couple of changes that can be made to improve things for this model:
First, if you change the type of the pattern from "Pattern Features" to "Pattern Faces" it will help a lot, but it still can take up to 5 minutes even with this change. So, a different approach can get better results.
One approach that I tried, is to use Web instead of Pattern. I created this sketch (using Sketch pattern):

And then used Web to create the grill:

This approach takes the time to compute the grill down to less than 2 minutes. Still slow, but probably acceptable. This version is attached as "Vertical Sign.web.f3d"
But the best approach, so far, is to use Body Pattern to create this grill.
Create two of the ribs of the grill, as separate bodies:

Then, pattern these bodies, all as separate bodies:

and, combine them into one body using a Combine feature:

This entire model computes in under 5 seconds! It is attached as "Vertical Sign.body_pattern.f3d"
I hope that this can get you past these problems, and thanks for pointing out the problem in Fusion.
Jeff Strater (Fusion development)
Jeff Strater
Engineering Director