HO MODULE AND TRACK STANDARDS AND RECOMMENDED PRACTICES
Module construction must accommodate ease of erection and compatibility with other club modules to facilitate setting up layouts at shows.
Poway Station subscribes to all National Model Railroad Association (NMRA) Standards and Recommended Practices (RPs) with the following specific exceptions and additions. NMRA Standards and RPs have not been reproduced here, but are available at the NMRA web page, http://www.nmra.org/standards/ . Printed copies of the NMRA Standards and RPs will be available for review at most Poway Station club meetings. It should be noted that the NMRA Is currently revising the Standards. These standards will be modified as needed to reflect future changes made by the NMRA.
These Standards currently apply to HO scale only. Other scales have their own Standards.
Modules built and operated by members before the adoption of these Standards
in this format are automatically exempted, although any reconstruction should
attempt to bring the module into conformance. Non-conforming modules owned
by new or prospective members will be evaluated by the Standards Committee,
and an accommodation will be negotiated. Non-members wishing to operate
their modules with Poway Station must provide suitable transition to Poway
a.. Straight Modules: The standard Poway Station straight module shall be 48" by 30".
1) The maximum module depth remains 36".
2) The minimum module depth is 12".
b. Corner Modules: The standard Poway Station corner module shall be 48" by 48".
1) The module may have the inside and outside corners cut off to form a hexagon shape, provided appropriate bracing is included to maintain stability of the module.
2) The module may have a radius on the viewing edge, provided
a) appropriate bracing is included to maintain stability of the module,
b) appropriate mounting is provided for protective Plexiglas.
c. The standard skyboard height shall be 11.5 inches above the table base height. Other heights will be allowed, so long as the module owner provides suitable transition to standard height skyboards.
a. JOINTS: All rail joints, except those at the drop-in connectors and insulated joints, must be soldered. It is the intention of this standard that no track joint rely on the rail joiner to provide electrical continuity.)
b. SIZE: Track shall be Code 83 nickel-silver for all mainline track. Should a member wish to use a different size rail, it must be brought back to Code 83 within seven inches (7") of the end of the module that will interface with other members' modules..
c. POSITION: Track centerline position for all tracks shall be measured from the front (viewing edge) of the module, BEFORE fascia (see section II.A.1.c)1) below) is mounted. For modules that extend to the front, centerlines shall be measured from the indicated standard front edge.
d. MINIMUM RADIUS: Minimum radius for 30" for mainlines, but all curves should be as broad as possible.
a. LENGTH: Modules must be multiples of two feet (24") long. Depth is limited to 36 inches maximum, but may be as narrow as 12", provided the module owner provides for suitable transition to, and joining with, standard modules.
b. PAINT: Mixing data for all paints can be obtained from the scale chair.
1) All flat-topped modules must be painted a base coat of the standard club beige undercoat, Valspar #326-3 Wheeling," or equivalent, available at Dixieline. (Equivalent paints may be available by color matching at Frazee or Home Depot. The Valspar originally selected has been found to be "sticky" when compressed, even after several months of curing time.) A limited amount of this paint is available from the club.
2) All skyboards must be painted a base coat of the standard club sky blue (the name and formula for this paint will be inserted into the final version), to be supplied by the club. This should be applied before any mountains, trees, clouds, etc. are added to the skyboard.
c. FASCIA: Modules must have a fascia board mounted on the viewing edge of the module to accommodate mounting the protective Plexiglas used by the club at shows. The fascia must create a slot two inches deep, measured from the module table top, for the Plexiglas to be inserted between the fascia and the main module frame. Fascia must be set back from each edge at least 1/8" (total length of fascia = 39.75" maximum), so as not to interfere with the joining of the modules.
d. ENDS: Module ends must be perpendicular to track and table top.
e. TOP: Module top must not overhang ends.
a. No permanent magnet uncoupling ramps are allowed in mainlines or mainline passing sidings. (Use electro-magnetic type.)
b. Mainline ballast must be gray, a 50/50 mix of medium and fine.
II. RECOMMENDED PRACTICES
a. LEGS: Each module shall have at least on set of legs that raise the module to the standard height. Construction is not specified, provided legs are sturdy, provide the required adjustment, and do not interfere with neighboring modules.
b. CONSTRUCTION: modules can be of any material, provided such modules are sturdy, can be connected reliably to neighboring modules, and do not present a safety hazard to members assembling the layout. Questions shall be ruled on by the Board at the recommendation of the Standards Committee.
c. BOXING: Modules should be boxed for protection in storage and transit, in pairs where possible.
d. END CAPS: Box ends caps should have furniture glides installed on at least one end, to facilitate sliding across floors, in the trailer and at set up sites, without damaging the floors. Glides should raise the module box off the floor sufficiently to allow the mounting bolts to clear the floor. Alternatively, mounting bolts could be counter-sunk, so as not to protrude from the box end cap.
a. GRADE: Maximum mainline grade is 0%. No grade is allowed in mainline or mainline passing sidings.
b. INDUSTRIAL TRACK RADIUS: Minimum industrial track radius is not specified, provided reliable operation is maintained.
c. HORIZONTAL CLEARANCES: Minimum horizontal clearances shall be at least six scale feet from the track centerline for tangent track. On curves, clearances must accommodate the longest equipment, currently 89' passenger cars and autoracks. This equipment should be tested on the curve before track is permanently installed.
d. VERTICAL CLEARANCES: Minimum vertical clearance shall be at least 3.5 inches above the railhead. This is more than adequate for AREMA Plate H dimensions, and is required to clear double-stacks.
e. TANGET TRACK: Minimum parallel tangent track for HO shall be 2.5 inches (total from module edge = 7.0"). (This means the track must not contain any deviation, such as the beginning of curves or turnout points, sooner than 7.0 inches from the module edge.) Modules constructed prior to the adoption of these standards will be granted an exception, provided operation is reliable.
a. JOINERY METHOD: Modules should be joined by 1/4 x 20 (eye) bolts and T-nuts through holes drilled in the ends of the modules. The location of the holes will be marked by the Standards Committee. The correct 9/32" holes can be drilled by the Standards Committee if desired.
b. BACKS: Module parts, such as legs and skyboard backs, that are not meant to be viewed by the public should be painted flat black.
a. Any turnout located in a mainline or mainline passing siding should be at least #6. Modules owners should strive to avoid "S" curves, that place undue stress on equipment and contribute to derailments, at all turnout locations.
b. All turnouts in the mainline and mainline passing sidings should be powered. Selection of switch machine is at the discretion of the module owner.