That's only 14.14" center rail radius, FasTrack O-31 is 15.5" center rail radius with 4" wide roadbed.
Rob, are you sure the roadbed is 4” wide and not 3.5”? I have RealTrax and it’s 3” wide. I just watched a video comparing the 2 (one on top of the other) and it didn’t look like a full inch difference. Then I saw that Amazon lists the dimensions for a 5” section as 5”x3.5”.
My calculations say center-to-center distance of an oval is 31”. Roadbed adds 3.5” (1.75” on each side) making the overall width 34.5”. This means the roadbed will be .75” from the edge of the table. The track center rail will be 2.5” from the edge arguably leaving enough clearance for a barrier around the outside of the table.
The bottom line is that an O31 oval will fit on a 36” table and will leave a little room.