HOn30 Home Depot
HOn30 Modular standards

Updated 2-Dec-99

Here is our latest revision of our module standards. I tried to clean up the way it reads and to include answers to many of the questions that have come up over the past two years. We are still working out wiring and scenery ideas as the folks involved discuss their desires and share their experience.

We now have a group in New England of 9 active members and a few others that are interested but not yet committed to building. We will have a few modules at the Whitman Two Foot Meet in November 1999 and are planning other activities for the coming year. Another group has formed in the Midwest that is working toward having a module display at the Two Foot Meet in Salem, Ohio in April 2000 and the Narrow Gauge Convention in St. louis. MO in 2000. With any luck some of us in New England will join the Midwest group in St. Louis and they will join us in Providence, RI in 2002. There are also a few other modelers building to these standards in various parts of the US who will join us when they can.

Anyone that is interested in building a module to these standards please contact me at jamesmpii@aol.com or 518-346-6058 and I will try to answer your questions and also try to hook you up with others in your area.

--Jim Pasquill

MODULE HEIGHT

Height to the top of the rail is 48".

Most of the modules built so far have 45"-long legs with a 1" standard extension on an adjusting bolt (so it can go up or down about 7/8"). This is a 46" leg, which leaves 2" for the module top, track support, and track. Placing the rail height 2" above the leg height leaves room for scenic features below the track, and other flexibility such as a spur with a downgrade.

TRACK LOCATION

The center of the mainline track is 6-7/8" from the BACK edge of the module measured from the face of the backdrop. If you want to build a module with your track running through the backdrop to a staging area you may, as long as the visible portion of the mainline crosses the ends at 6 7/8" from the face of the backdrop.

Having the mainline toward the back allows placing the interesting stuff -- spurs, industries, depots, turntables, and so forth-- in front of the mainline and toward the viewer and reinforces the impression that the trains are running through the scenery instead of in front of it.

The mainline must cross the module boundary at a 90-degree angle except as noted below.

Module pairs that will always be mated may have a non-standard setback at their internal boundary and may cross their internal boundaries at a different angle.

TRACK and JOINER-TRACK SECTIONS

The top of the rail must be 48" above the floor, and the joining section must be code 70 except as noted below.

Minimum mainline rail size is code 55, with code 70 recommended. You may use N gauge track if Hon30 is not available to you.

The mainline must end 3" from the end of each module requiring a 6" code 70 joiner section. Currently most of us are using Shinohara or Microtrains N-gauge flex-track for the joiner. If code 70 HOn30 flex-track becomes readily available we will switch to it.

Owners of module pairs that have the same track code other than code 70 may use a joiner track of the same code. For example, there is no need to have a code 70 joiner between two code 55 modules if the owners supply a code 55 joiner. Also, local groups can choose a different size rail for the joiner if the majority of members are using a particular rail size. However, code 70 was chosen as a good compromise between those who use code 55 rail and those who use code 80/83.

We use the NMRA N-gauge standards gauge for track and turnouts.

TRACK AREA CLEARANCES

Parallel tracks must be at least 1 ½" apart on centers, with 2" preferred.

All parts of road crossings should be 1/64" lower than the rail top. Flangeways through crossings should be the same as turnout frogs which means to NMRA N standard.

Building and platform clearances should be a full HO scale 36" (10.5mm) from the outer edge of the outer rail.

MINIMUM RADIUS and GRADES

Minimum 18" radius for the mainline and passing sidings. For any other track the radius is up to owner but keep in mind that the tighter the radius the fewer cars and locomotives that will be able to run on parts of a module.

Turnouts: Minimum No. 5 or 6; and the mainline should go through the straight leg of switches.

Grades: Allowed, but only on an individual's modules or on modules designed to be used as sets. This allows an individual or partners to create a switchback or short grade providing the module sets are long enough. The net grade allowed is "0".

COUPLER and WHEEL STANDARDS

We use the NMRA N gauge standards gauge for wheels, Microtrains couplers and the Microtrains MT-1055 gauge for coupler height. Rolling stock to be used in a consist with other owners rolling stock must have body mounted couplers.

BACKDROP HEIGHT

Backdrops should extend at least 12" above the track height. 14" is better and we are encouraging folks to accept 14" as the standard.

CONSTRUCTION MATERIALS

Modelers may use ANY materials they wish as long as the modules can be mated.

The groups in New England and the Midwest are discussing standard scenery contours for module ends. Contact us for details. The standards for scenery contours will be only recommendations.

MODULE CONFIGURATION and SIZE

The standard is a single-track mainline. An individual can have any number of tracks crossing the internal boundaries of modules that are always to be mated to each other.

Module width: minimum 20"; maximum 30", 24" is recommended. Local groups can allow deviations according to their own desires. For sake of esthetics, it is recommended that modules wider and thinner than 24" have front ends contoured to bring the module in or out to 24".

Length can be variable, but 4' is about right and is recommended by NTrak. While a 4'-long scene in HO scale doesn't allow for much scenery and track, pairs of 4' modules can make excellent 8'-long scenes. 3' modules are allowed if that is all you have space for. Paired 3' modules offer more flexibility and are particularly easy to transport if stacked.

Our modules are operated from in front (facing the module) so turnout and electrical controls should be in front.

Corner standards: We follow NTrak practices with variances for our setback, and with the above stated height and radius standards. Local groups can decide if they want to create layouts that have inside or outside corners, or use loops at the end of point to point layouts.

JOINING MODULES

We use a standard 3" C-clamp, per NTrak. Top of rail to inside edge of the spine of C-clamp not to exceed 4-1/2".

Modules designed by individuals or partners to be used as pairs or sets can use a different method of joining their modules.

PECO CODE 80 TO CODE 70 TRANSITIONS

Here is the method you can use to bring code 80 Peco track down to the standard code 70 joiner. You can a similar procedure to bring code 55 up to the standard code 70 joiner.

To bring the Peco code 80 track on the module down to code 70 for the transition, cut the rail out of the Peco code 80 flextrack for the last 2", but leave the ties. Slip a rail joiner halfway onto the end of the code 80 rail, then flatten with pliers so it's roughly .010" thick. Solder code 70 rail on top of joiner and to end of code 80 rail, then file smooth. Paint it, and you'll have a hard time even seeing it after the track is ballasted. If you want to be fussy, slip a strip of .010" Evergreen styrene under the Code 70 rail to shim it up against the molded flextrack spikes. Code 70 module to module joiner sections can be made by replacing the code 80 rail in Peco flextrack with code 70 rail.

WIRING STANDARDS

For the most part we follow NTrak wiring practicess but our wiring practices are evolving. Please contact us for the latest. We use NTrak recommended connectors, Radio Shack part numbers 274-201a and b. Part 274-201ba was recently renumbered by Radio shack as part 274-202 and as of this writing both numbers appear on the store shelves. The front rail should have a red wire, back rail should be green. Red wire is connected to the large fork on the plugs, green to the small fork. The female plugs should go to the left when facing your module and the male plug then goes to the right. The connectors should be wired to a terminal strip mounted under the module and your green and red track lines should connect from the terminal strip to your track. A power pack can be connected to any module via the terminal bar.

Currently most of the active members have their modules wired for only one cab. We are recommending 2-cab block control with blocks controlled by DPDT center off switches. The switches should be clearly marked for A main cab and B local cab.

If you elect not to build in electrical blocks or you use dcc you must provide for the mainline to be isolated. As a minimum, sidings should be controlled by the turnout points, however controlling them by electrical switches is better. If you do install electrical switches to control your sidings you might as well choose DPDT switches which will allow upgrading to two cab control in the future without changing switches.

NTRAK MANUAL

The NTrak Manual can be ordered for $1.50 from NTRAK C/O Jim Fitzgerald, 1150 Wine Country Place, Templeton, CA 93465. Also, check the NTrak home page at http://www.mv.com/users/kgg/_ntrak/ . While on the Internet also check out the OneTrack site for additional ideas, http://www.nvntrak.org/nb/onetrak.htm .
These standards were developed by the members of the HOn30 mailcar based on existing modules built by Jim Pasquill and Chris McChesney. The text was written and edited by Bob Hayden and Jim Pasquill

You can get a sneak preview of Dave's half done module here.
Please also check in on the module groups listed Here.

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