How much space do you need for a Minitrix layout?
Benjamin | TrackDrawer.com · published 7 November 2026
For a closed loop in Minitrix you need a 55 x 55 cm baseboard. A loop with a passing loop fits from 85 x 55 cm, and on 120 x 60 cm the Auto-designer already lays double track all round with a siding and a small yard. On 200 x 100 cm it becomes double track on R4 and R3 with more than 10 m of track.
We measured this with the TrackDrawer Auto-designer, using an ordinary stock of Minitrix and a 5 cm clear margin around the board. Below you can see what fits on each size and why.
Why Minitrix is so compact
Minitrix is N gauge on 9 mm track. The track has no wide roadbed and is 16 mm wide seen from above. The tightest curve, R1, has a radius of 194.6 mm. Above that the radii step up by exactly 33.6 mm, the system's track spacing: R2 228.2, R2a 261.8, R2b 295.4, R3 329 and R4 362.6 mm. After that come R5 and R6 at 492.6 and 526.2 mm.
Because the steps are so small, you can lay many loops side by side in Minitrix without the board getting much deeper. The measurements show it.
Outside width per radius
A full circle sets the depth of any layout. The outside width is twice the radius plus 16 mm of track width; for the baseboard add 2 x 50 mm of margin.
| Radius | Radius in mm | Circle outside width | Board with 5 cm margin |
|---|---|---|---|
| R1 | 194.6 mm | 405.2 mm | 50.5 cm |
| R2 | 228.2 mm | 472.4 mm | 57.2 cm |
| R2a | 261.8 mm | 539.6 mm | 64.0 cm |
| R2b | 295.4 mm | 606.8 mm | 70.7 cm |
| R3 | 329 mm | 674 mm | 77.4 cm |
| R4 | 362.6 mm | 741.2 mm | 84.1 cm |
| R5 | 492.6 mm | 1001.2 mm | 110.1 cm |
So each step costs 6.7 cm of depth. What that means for long coaches is covered in the tightest curve radius in N.
The smallest loop: 55 x 55 cm
According to the table, R1 needs at least 50.5 cm. Measured in 5 cm steps that becomes a 55 x 55 cm board, on which the designer lays an oval on R1. A circle alone is a short run; in practice you want more width for straights.
A passing loop: from 85 x 55 cm
The standard Minitrix turnout (14951 left, 14953 right) is 104.2 mm long and diverges on R1 over 24 degrees. With the matching curve 14914 the second track lies 33.6 mm beside the first. On the straight side you add the 54.2 mm straight 14906, so both sides are 158.4 mm long. That is short: a passing loop costs barely 16 cm at each end.
That is why the Auto-designer found a loop with a passing loop on just 85 x 55 cm: "Station with two platform roads on R1, plus 2 sidings", with 34 pieces and 2.72 m of track. At 65 cm deep, 85 cm remained the smallest width. For comparison, the same idea in Märklin C track needs 160 x 90 cm; see how much space for C track.
What fits on common sizes?
With the same Minitrix stock we had the designer search several board sizes with three goals: continuous running, several trains with a station, and variety. The table shows typical suggestions per size.
| Board | What fits (examples) | Pieces | Track |
|---|---|---|---|
| 85 x 55 cm | station with two platform roads on R1, plus 2 sidings | 34 | 2.72 m |
| 85 x 65 cm | station with two platform roads on R1 | 28 | 2.25 m |
| 120 x 60 cm | double track R2/R1, plus siding and yard | 49 | 6.59 m |
| 120 x 60 cm | station on R2, plus 2 sidings | 44 | 4.86 m |
| 150 x 80 cm | double track R2b/R2a, plus siding and yard | 68 | 8.52 m |
| 150 x 80 cm | double track R2a/R2 with crossover, plus passing loop and yard | 69 | 8.40 m |
| 200 x 100 cm | double track R4/R3 with crossover, plus siding and yard | 109 | 10.23 m |
| 200 x 100 cm | dogbone on R3, plus siding and yard | 69 | 7.13 m |
Three things stand out:
- Double track from 60 cm deep. Double track on R2 and R1 is 472.4 mm across the outside. On 120 x 60 cm the designer lays it with a siding and a yard inside, 6.59 m of track in total.
- The radii grow with the depth. At 80 cm deep the designer picks R2b and R2a, at 100 cm R4 and R3. Wider curves run more smoothly and look better with long coaches.
- Crossovers. From 150 x 80 cm double tracks with a crossover appear, so a train can move from the inner to the outer loop. Why those tracks are exactly 33.6 mm apart is explained in track spacing.
A board you can put away
Minitrix suits layouts that do not have to stay up all the time. A 120 x 60 cm board with double track fits under a bed or behind a cupboard and can be carried with two hands. Bear in mind that light rolling stock and small wheels need clean rails; a layout stored in the dust needs a quick clean before you run trains.
For a permanent layout the usual reach applies: you can comfortably get to the track up to about 60 to 70 cm from the edge. An N layout 100 cm deep is therefore best freestanding or accessible from two sides.
Frequently asked questions
Does a Minitrix layout fit on a 30 cm windowsill?
Not as a loop: even R1 is 405.2 mm across the outside. On a strip that narrow, build an end-to-end line or a small shunting yard without a loop.
Which radius should I choose on a board 80 cm deep?
With a 5 cm margin, 70 cm is left for the outside width. R2b (606.8 mm) fits with room to spare; R3 (674 mm) just fits. On 150 x 80 cm the designer chose double track on R2b and R2a.
Your own baseboard
Look at the Minitrix plans in the Railfolio, or enter your own baseboard and stock and let the Auto-designer lay a plan that really fits.