a number 4 turnout, lets say it takes 4 inches from point to frog, vs 1 inch out from frog to 1 inch width breadth of the frog rails.
The flangeway gauge is critcal in finding the point location.
Works for me.
I don’t even try to figger if a turnout I make is #4, #6, I just work the curve I need, and fit the rails.
The turnout number is actually determined by a ratio measured from the place in the frog where the rails cross, then measure away from the points. If the ratio is 4 to 1 (four feet from the crossing place, the rails are 1 foot apart) it’s a number 4 turnout. One foot apart at 8 feet from the crossing place, it’s a number 8. Etc.