Fast track curve spacing question

[SleeperN06]

I noticed that Fastrack comes in 036 and then the next size is 048 and I want to know if I’m going to have a problem running MTH Realtrax 042 around the 036 Fastrack. I placed the two tracks next to each other and the roadbed touches perfectly all the way around, but I’m wondering why does Lionel skip the 042” diameter and go straight to 048”?

Is it because of clearance problems?

I don’t know if it maters but I’ll be running the Lionel Polar Express and the Hogwarts Express side by side and I don’t want any incidents. I already have the 042 Realtrax and I like that it parallels the 036 Fastrack so nicely.

[overall]

I think I read somewhere that Lionel wanted a 6 inch space between tracks. That's why they went with the 036, 048 etc. You might try just building a temporary floor layout and actually run the trains over it slowly to see if they do conflict or not.

George

[phillyreading]

To be sure about spacing rerquirements, have the two engines in question run side by side on the curved sections and see if the cabs of the steam engines hit or not.  I have found that larger steam engines like a 2-6-2 and large diesel engines like an SD-45 need extra space on curves not to hit on parallel curve tracks, also extra long freight cars like a six or eight axle depressed center need more clearance on curves.

Lee F.