Piece of cake in Templot! There's no need to cut the middle out, you can do this in a single template, and it needn't be straight, it can be curved track. In fact it can even be a transition curve before you begin, and you can still slew one end sideways with respect to the other. What's more there are two different modes for slewing, using different maths, and mode 2 allows you to adjust the shape of the S-curve with the mouse.
It's easy to do - simply click Slew in the menu and then with the mouse adjust the start point for the slew along the track, the length of the slewing zone, and the amount of sideways slew needed. Or you can enter this data directly as numbers, in mm, inches, or prototype dimensions if you prefer. There are some notes and diagrams at: (Templot isn't anything like CAD, so experienced CAD users should look away now!)
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