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MS-1.0 Module Standards, Standard Gauges
Modules built prior to the acceptance of these Standards will be exempt from these standards. However, if non-conforming modules are to interface with conforming modules, a transition module will be required to accommodate any difference in trackage, electrical, etc.
| Gauge | Height from Floor to Top of Rail | Hand Laid or Commercial Rail Code | Track Clearances H=Horiz V=Vertical |
Interface Track Center Lines from Module Front | Track Setback From End of Module | Center Lines on Curves | Track Centers for Parallel Tracks |
|---|---|---|---|---|---|---|---|
| Z | 40" (1016mm) | 60 (40) n1 | H=15/32" (12mm) V=1-19/64 (33mm) |
(*) 5" (127mm) 6" (152mm) | 2-3/16" (55mm) | 1" (25mm) | 1" (25mm) |
| *Two through tracks required | |||||||
| N | 40" (1016mm) | 80 n5 55-70(*) | H=19/32" (15mm) V=1-21/32" (42mm) |
4" (101.6mm) 5-1/2" (139.7mm) 7" (177.8mm) | 2-15/32" (62.7mm) | 1-1/2" (38.1mm) | 1-1/2" (38.1mm) |
| *Three through tracks required, Mainline. One through track required, Secondary | |||||||
| TT | 40" (1016mm) | 70 | H=3/4" (19mm) V=2-3/16" (56mm) |
4" (101.6mm) 5-3/4" (146mm) 9-1/2" (241mm) | 3" (276mm) | 1-3/4" (44.5mm) | 1-3/4" (44.5mm) |
| *Two through tracks, Mainline. One Through track, Secondary. | |||||||
| HO | 40" (1016mm) | 100 | H=1-1/32" (26.2mm) V=3" (76.2mm) |
5" (127mm) 7" (177.8mm) | 4-1/2" (114.3mm) | 2-1/2" (63.5mm) | 2" (50.8mm) |
| *Two through tracks required, Mainline. Others optional. | |||||||
| OO | 40" (1016mm) | 100 | H=1-3/16" (30.2mm) V=3-7/16" (87.3mm) |
5" (127mm) 7-3/8" (187.3mm) | 4-1/2" (114.3mm) | 2-5/8" (66.7mm) | 2-3/8" (60.3mm) |
| *Two through tracks required, Mainline. | |||||||
| S | 42" (1067mm) | ** | H=1-3/32" (27.8mm) V=4-1/8" (104.8mm) |
6-1/8" (155.6mm) 8-7/8" (225.4mm) | 2" (50.8mm) | 3-1/2" (88.9mm) | 2-3/4" (69.8mm) |
| *One or two mainlines optional. Check local NASG group for details. | |||||||
| O | 42" (1067mm) | 148 | H=1-7/8" (47.6mm) V=5-1/2" (139.7mm) |
6" (152.4mm) 10" (254mm) | 2" (50.8mm) | 5" (127mm) | 4" (101.6mm) |
| *Two mainlines required. | |||||||
| High Rail Tinplate | 36" (914mm) | O Gauge Tinplate | H=5-1/2" (39.7mm) V=1-7/8" (47.6mm) |
4" (101.6mm) 7-1/2" (190.5mm) | 5" (127mm) | 21" n2 (533.4mm) 35" n3 (89mm) |
3-1/2" (88.9mm) |
| *Two mainlines required. | |||||||
Module lengths for all scales shall be in 2' increments with 2' allowed as
transition module. (n4)
* All track clearances are per S-7 and include all other pertinent Standards.
** No rail code recommended, S scale only use RP-3 for track gauge.
*** Hand laid track in N scale and smaller is very fragile and easily damaged
in handling and is not recommended.
**** Recommended but not required S scale only.
- NOTES: (n1 = note 1., n2 = note 2., etc.)
- (1) If code 40 rail is used, it must be brought back to code 60 rail 2" from interface.
- (2) Inside radius on corner.
- (3) Outside radius on corner.
- (4) NSG has larger modules in 2' increments up to 24'.
- (5) NTRAK uses Atlas or Peco code 80 rail. Code 55-70 is allowed within module but must be brought back to code 80 at interface.
(*) denotes change from previous issue.