Our wood train set from Ikea, the Lillabo, doesn't come with any x-crossing pieces. Other sets with x-crossing pieces are probably compatible, but I choose to make an x-crossing piece myself. I did this both to familiarize myself with the workflow of design in Fusion to making on the Othermill, and also as a first step of a project to make a custom wooden train set that spells out my kids' names.
Step 1: Measure and Design X-crossing
I measured the existing tracks and built a Fusion model, which is available here and is attached to this step.
Step 2: Generate Tool Paths
I used the CAM workspace in Fusion to generate toolpaths to cut the x-crossing on the Othermill.
I created three toolpaths for use with an 1/8'' flat end mill: two pockets and one contour. I found a piece of plywood that was approximately the same thickness as the train tracks, which saved an extensive facing operation. The .nc files are attached. These are only specifically useful if you have the exact same machine, tool, and material, but might be generally useful if you're curious about toolpaths for the Othermachine.
Step 3: CNC Cut
Here's the Othermill cutting the track and the finished piece. All three operations took about an hour.
Step 4: Connect the Tracks
I cannibalized plastic connectors from other pieces of track, and invited a three-year-old to make a train track. The curved pieces of track set a radius which I wanted the x-crossing to properly match. There's enough slop in the connections that this was easy.
Chugga chugga choo choo!