How to combine / join Cube Facts

Hello Community.

I have three cubes. Two of them share three dimensions (one of them a Date Dimension), the third one only shares two (one of them a Date Dimension) with the other ones.
The cubes are like that:

Cube #1 defines operational parameters of a maschine, like hours it run per day. The dimensions are Date and Maschine Specifications.
Cube #2 defines problems per maschine, per day. The dimensions are Date, Maschine Specifications and Error Code Specifications.
Cube #3 is quiet similar to cube #2, it only differs in the facts, the dimensions are the same.

The Fact Tables have foreign keys to the same Dimension Tables. As standard aggregation, the fact fields should all get summed up.

I read about virtual cubes and shared dimensions but I'm missing an example how to build the cubes in Schema Workbench.

My approach was to build a schema, which contains three cubes and the thee dimensions. I think if I add the Dimensions directly to a Schema but not to a cube, it's a shared dimension, right? I added "Dimension Usage" to the cubes.

But now I don't know how to build the virtual cube or if this approach is the right one at all? I want to be able to see dependencys between the facts of the three cubes like: How did problems, which are logged in cube #2 affect the operational parameters logged in cube #1.

Thanks & Regards!