I've been working on a 3D printed roller coaster for the past year. In this video I explain my process of creating track. Keep in mind this is just how I do it, if you have a different way of doing it please let me know in the comments!

4.572 Number Explanation:
In the video I can't remember how I came up with that 4.572 number. But I think I figured it out. When you first import in the track splines, Fusion 360 reads the numbers you set in the extractor program as millimeters. So when you set the left, right, and bottom splines to 4.572, Fusion is going to put them 4.572mm away from the center spline. However, for the number you put into the No Limits spline export which determines the distance between points (0.39m in the video). Fusion reads that number as 3.9 mm for whatever reason. Because of this discrepancy in how Fusion reads the two numbers, it can cause weird scaling if set up improperly. With the verification method using SketchUp, a bunch of trial and error, and a bit of math, this shouldn't be too much of a hurdle if you want to change your track gauge and/or scale. But hopefully this helps clear some things! As I said the Spline extractor program has always worked a bit strange for me and you might not have these problems.

Link to Spline Extractor Program: https://github.com/Tello3/NL2SplineTr...

00:00 Importing spline points into Fusion
09:49 Modeling track spline in Fusion
24:24 Modeling cross tie
30:46 Modeling spline and cross tie as one
32:23 Modeling supports
40:17 Verifying the Fusion model is accurate to No Limits
48:04 Cinematics