There is no way to create an Switch Tracks. I use a standard rail (8 pieces) and a wooden canvas (1 piece).
There are no recipes for creating any Switch Tracks.
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whatisthat-wq commented
I have the same problem as well......
whatisthat-wq commented
I found the solution
Apparently you can craft a spike maul, and right-click on the track to turn it into switch track/junction track.