What T-TRAK is
T-TRAK is a modular model railway format built on a simple premise: a model layout should fit on a tabletop, travel in the boot of a car, and connect to other people's modules without a phone call beforehand. Each module is a small, self-contained baseboard — usually a single straight section — with the track already laid, the wiring already run, and the scenery already finished.
Modules click end-to-end into a layout. There is no benchwork to assemble at the venue, no clamps, no soldering at module joins, and no need to align legs to a common datum. The module sits on its own adjustable feet on a folding banquet table, the next module sits beside it, and the Kato Unijoiners do the rest.
The format is dual-track from the outset. Two parallel main lines run through every module, so a layout can run two trains continuously without a single point or crossover anywhere on the system. Add corners at the ends of a row of straights and you have a closed loop in minutes.
Because each module is small — a single straight is roughly the size of a long hardback book — a builder can finish one in a weekend, store ten of them on a shelf, and bring whichever ones suit the current scene. The barrier to entry is a sheet of MDF, four pieces of Kato Unitrack, and an afternoon.
An Australian single straight is 308 mm wide and 300 mm deep. International single straights are the same width but only 210 mm deep.
Modules sit on standard folding tables. Adjustable feet handle the inevitable wobble. No frames, no trestles, no on-site carpentry.
Two parallel main lines run through every module. A layout runs two trains continuously without needing any pointwork.
Like LEGO, with rails
The clearest way to explain T-TRAK to a newcomer is to compare it to LEGO. The standard LEGO 4×2 brick has a fixed footprint and a fixed stud spacing. Almost every other brick in the system — the slopes, the plates, the wheels, the windows, the specialist parts — is designed to connect to that 4×2 brick directly, or to connect through a converter piece that itself connects to the 4×2.
T-TRAK applies the same idea to a modular tabletop layout. The standard single straight is the 4×2 brick. Doubles, triples, corners, junctions, three-way modules, and the smaller Mini-T variants are all designed to click into the same end-of-module geometry. The track ends in the same place, at the same height, at the same spacing, with the same Unijoiner pattern, every time.
The consequence is the thing that makes T-TRAK work as a community format. A layout assembled on the morning of an exhibition can include modules built across many sheds in many states, by people who have never met, without anyone needing to call ahead. If the geometry is right, the modules join. If a module is wrong, you find out at the joint and you fix it at the joint — the rest of the layout is unaffected.
This is also why the standard exists at all. The standard is not a list of preferences; it is the contract that makes inter-operability possible. As long as every builder honours the end-of-module geometry, the polarity convention, and the height datum, what happens between the joins is entirely up to the builder.
The single straight is the foundational module. Everything else in the T-TRAK ecosystem — corners, doubles, junctions, Mini-T, HO/OO, TT — is designed to connect to it through the same end geometry.
Where T-TRAK came from
Japan, around 2000
The T-TRAK concept was first proposed in Japan around the turn of the millennium. The original idea pulled together two threads that were already in the air: the existing NTRAK modular standard, which used long heavy modules and a 4-foot leg height, and Kato's then-new Unitrack sectional system, which made it possible to lay reliable, repeatable track in a few minutes without ballast or hand-laid joints.
Combining the two produced something different in character to NTRAK: short, light modules that lived on a tabletop instead of on dedicated trestles, and that used the geometry of a commercial track product as the unifying spec.
Lee Monaco-FitzGerald and the international community
The N-scale form of T-TRAK was developed into an international community standard largely through the work of Lee Monaco-FitzGerald in the United States. The 210 mm-deep international single straight, the polarity convention, and the early documentation that travelled outwards through clubs and forums all trace back to that effort.
From there the format extended outwards: HO/OO scale modules with a wider footprint, the smaller Mini-T format for compact spaces, and most recently TT-scale modules added in the 2023 addendum. The Australian guidelines, edited by Andrew George with contributions from modellers in several states, codify the local conventions.
Why an Australian standard exists
If T-TRAK is an international format with an international standard, the obvious question is why Australia maintains its own standard alongside it. The honest answer is that Australia is an island. The materials at the local hardware store are not the same as the materials at the equivalent shop in Tokyo or Texas. The sheets of MDF and ply come in metric thicknesses and in panel sizes set by the local industry. The fasteners, the adjustable feet, the trim pieces — they all come from a slightly different parts bin.
The layout we set up at a hall in Bendigo is also shaped by the boot of the car we drove in. Australian club meets pull modules from across a state and sometimes across the country. The road trip from Adelaide to a meet in Melbourne, or from Brisbane down to Sydney, is part of the design constraint. Modules need to survive the drive, fit the storage we have, and use materials we can actually buy on a Saturday morning.
The most visible deviation from the international standard is the depth of the module. International T-TRAK N-scale single straights are 210 mm deep. The Australian standard is 300 mm deep. The extra 90 mm at the back of the module is room for a layered scene — a road behind the back track, a row of buildings behind the road, a hillside or a sky-board behind that. Australian modellers asked for the depth and the standard codified what was already happening.
The crucial point is that the track geometry is identical. The track sits at the same place on the module, at the same height, with the same overhang at each end. International and Australian modules join cleanly to one another. The deeper Australian module simply has more scenery behind the rails. A visiting international layout slots straight into an Australian meet without modification, and an Australian module will run at an international meet — it just looks a little deeper from the front.
Australian modules are 300 mm deep instead of the international 210 mm. The extra depth lives behind the back track and is reserved for layered scenery.
Track geometry, height, polarity and Unijoiner pattern match the international standard exactly. Modules from either standard click together at a meet without adjustment.
Who builds T-TRAK
Beginners
The first module a new modeller builds is typically a single straight. The materials cost a pub meal, the carpentry is one weekend, and the result is a finished, runnable piece of railway that can be plugged into a club's layout the following month. School groups and youth modelling programs use T-TRAK for the same reasons. Retirees with limited bench space find the small modules easier on the back than a permanent layout.
Clubs across the states
Most Australian states have at least one active T-TRAK club or club program. Modules circulate between meets, between clubs, and between exhibitions. A state-level meet can pull together a hundred-module layout from twenty builders without anyone having to coordinate scenery themes in advance.
Exhibition builders
For experienced modellers, T-TRAK is a way to bring detailed scenes to a public audience without committing a permanent room at home. A junction module, a station module, an industrial siding, a coastal viaduct — each is a self-contained scene that can be exhibited, lent out, photographed, and rebuilt without disturbing the rest of a collection.
Anyone without a layout room
Apartment dwellers, renters, modellers in transition between homes, and anyone whose house isn't going to absorb a permanent layout — T-TRAK suits all of them. The format is portable by design and stores on shelving you already have.
Australian states and territories
Active T-TRAK builders, clubs and exhibition modules are present across all eight Australian states and territories. Local activity varies from year to year, but every jurisdiction has at least one builder or program in the ecosystem.
Five rules that hold the whole standard together
The Australian guidelines run to dozens of pages, but five rules carry the bulk of the inter-operability work. If a module honours these five, it will join cleanly to almost any other module in the system. Everything else in the standard is detail around these.
| 1 · Track overhang | +1 mm each end | The Kato track sits proud of the module edge by exactly 1 mm at each end so the Unijoiner has somewhere to bridge. |
|---|---|---|
| 2 · Module length | track length − 2 mm | The baseboard is 2 mm shorter than the total Kato track length: 1 mm of overhang at each end equals 2 mm shorter overall. |
| 3 · Polarity | BLUE → outer rail | The blue conductor of the Kato feed always lands on the outer rail of each main line. Reverse one and you short the layout. |
| 4 · DC feed cadence | ≥ 1 feed per 9 m | A DC layout needs at least one power feed every nine metres of running track to keep voltage drop within tolerance. |
| 5 · Track grade | 0% — level | Through-running track on every module is dead level. Gradients live inside specialist modules and never cross a join. |
If a module hits these five, it will join cleanly to almost any other module in the system. The remainder of the standards page expands on each of these and adds the practical details around them.
Where to go from here
If you are about to build your first module, the Standards page is the next step — it covers module dimensions, track geometry and the polarity convention in full. Construction walks through the carpentry from raw sheet to a usable baseboard. Electrical covers feeds, droppers and DCC. Scenery covers what goes on top once the woodwork and wiring are done.
If you would rather see T-TRAK in person before building, the Meets page lists active clubs and exhibitions around the country. Most clubs are happy to have a visitor at a setup day, and a setup day is the fastest way to understand how the modules click together in practice.