proper fastrack switch for spacing of proses diesel shed

Assuming that you're talking about crossover spacing on two tracks leading into the shed, O-31 switches will give you a 5  3/16" center-to-center spacing, which is about 5.48 ". All other FT switches will be close to the 6" spacing. Depending on how much length you have, you may be able to get it tighter with quarter curves or simply closing the two straights by hand if the two tracks terminate in or just beyond the shed.

PostmanBill

I played around with the trial AnyRail program and came up with the following measurements between centers for FasTrack.  Go to the track plans and layout building pages for more ideas and information.

Curve           One switch with reverse curve to parallel tracks.                Two Switches between Parallel tracks with diverging legs Joined

O-31                     5-1/8"     *(with 3 #6-81662)                                                                              5-1/4"

O-36                     6"     * ( with 1 # 6-12022, 1 #6-12023)                                             6"

O-48                     6 -1/2"                                                                                                                   6-1/2"

O-60                     5-1/8"                                                                                                                    5-5/8"

O-72          5-1/2"                                                                                                         5-5/8"

* Substituted for full matching curved track.   I did not use the small pieces that come with the switches/turnouts other than mentioned above

If you want to use curves wider than O-36, here's an option that offers 5.25 inch center rail spacing.

Left to right parts are: O-72 Wye, 1-3/8" half roadbed (two come with Wye), 1-3/8" straight, O72 half curve.

Thank you all for your help. Its time to hit the hobby shop!