Hidden staging and fiddle yards: trains out of sight
Benjamin | TrackDrawer.com · published 3 November 2026
Hidden staging is a group of storage tracks out of sight, below or behind the layout, where trains wait until they reappear on the visible part. A fiddle yard does the same job but sits in the open and within reach: there you swap trains by hand, usually at the end of a shelf layout. Both give your layout more trains than are on view at once, so something different comes past each time.
What hidden staging is for
On a layout where every train is in view, the same train keeps going by. Hidden staging changes that. The visible line seems to lead somewhere: a train disappears into a tunnel, and a while later a different one comes out. In the staging yard the trains wait their turn.
Two kinds are the most common:
- Through staging. The yard sits in the loop, usually below or behind the visible part. A train runs into a free track, waits, and leaves at the other end. Every train keeps running in the same direction.
- Stub-ended staging. The tracks end at buffer stops. Trains back out again or are turned by hand. This suits the end of a line and is really a hidden terminus.
If you want trains in through staging to change direction as well, add a reversing loop before or after it. On two-rail that needs isolated sections and an auto-reverser; how that works is explained in the reversing loop.
How much room does it take?
A staging yard is a fan of turnouts with parallel tracks behind it. With sectional track you build that fan as a staircase: after each turnout the diverging track swings out by one track spacing with a matching curve, and the next turnout follows on that track. Each step takes the length of one turnout group. Four tracks mean three steps at each end.
The table assumes trains of four vehicles, each the length of TrackDrawer's standard coach (H0 250 mm, N 136 mm). The outermost track is the shortest and still has to hold the whole train. The width is the room the tracks themselves take, without any margin.
| System | Tracks | Width | Fan per end | Through | Stub-ended |
|---|---|---|---|---|---|
| Märklin C track | 4 | 272.5 mm | 1.08 m | 3.16 m | 2.08 m |
| Märklin C track | 6 | 427.5 mm | 1.80 m | 4.60 m | 2.80 m |
| Minitrix (N) | 4 | 116.8 mm | 0.47 m | 1.49 m | 1.02 m |
| Minitrix (N) | 6 | 184 mm | 0.79 m | 2.13 m | 1.34 m |
Two things stand out. Staging is mostly long, not wide: in H0 the fans quickly cost more length than the trains themselves. And in N, four-track through staging takes less than half the length of the same yard in H0. The track spacing of sectional track is a minimum; in a hidden yard many builders space the tracks wider so a hand fits between them. Where that spacing comes from is covered in track spacing.
Below the layout: how far down?
If the staging sits below the visible part, the line has to drop far enough for a train to pass under the upper baseboard. TrackDrawer works this out for a helix from the NEM 102 clearance profile above the rail, the height of the track and the thickness of the baseboard. In H0 without overhead wires that is 55 + 6.6 + 10 mm, rounded up to 75 mm per level. In N it is 30 + 3.6 + 10 mm, rounded up to 45 mm.
To drop 75 mm at the default maximum gradient of 3 % you need 2.5 m of track, not counting the transitions. In N, 45 mm takes 1.5 m. If that length is not available, a helix (a spiral of curves) is the compact answer. Each turn climbs over the circumference of the circle:
| System and curve | Length of one turn | Gradient for 75 mm (H0) or 45 mm (N) |
|---|---|---|
| Märklin C track R1, 360 mm | 2262 mm | 3.3 % |
| Märklin C track R2, 437.5 mm | 2749 mm | 2.7 % |
| Märklin C track R3, 515 mm | 3236 mm | 2.3 % |
| Minitrix R1, 194.6 mm | 1223 mm | 3.7 % |
| Minitrix R2, 228.2 mm | 1434 mm | 3.1 % |
| Minitrix R2a, 261.8 mm | 1645 mm | 2.7 % |
With the default settings, then, a round helix in H0 with C track only works from R2 upwards, and with the track bed that is 91.5 cm across. In N with Minitrix it starts at R2a. A larger radius lowers the gradient and makes the helix wider.
The fiddle yard: trains by hand
A fiddle yard hides nothing: it is an open storage area where you swap trains by hand. It typically belongs to a shelf layout or a shuttle line, at one or both ends. There are a few forms:
- A fan of turnouts. Like stub-ended staging, but in view and within reach.
- A traverser. A deck with parallel tracks that slides sideways, so a different track lines up with the main line each time. No turnouts needed, and the deck is roughly as wide as the number of tracks times their spacing.
- A sector plate. A deck that pivots about one point and swings its other end in front of different tracks.
- Cassettes. Loose lengths of track in a channel that you lift off the layout, train and all, and turn round or put away.
Traversers, sector plates and cassettes are things you build yourself; they are not a piece of track in a sectional track catalogue.
Keeping it reachable
- Every track within reach. Even in a hidden yard a wagon derails now and then. Leave an opening, a lift-out section or enough room under the layout.
- No turnouts at the back in the dark. Put turnouts where you can see and reach them, or at least where you can get to them.
- Knowing what is there. In a hidden yard you cannot see which track is free. Occupancy detection on each track tells you, with a lamp on analogue or on your screen with digital control.
In TrackDrawer
You draw a staging yard in the editor as an ordinary fan of turnouts; the check reports tracks closer together than the NEM track spacing, collisions and gaps. With Pro you work in height: gradients with the percentage monitored, a crossing with less than 70 mm of clearance flagged as an error, a helix of real curves in one click, and tunnels to hide the entrance. Then 3D shows you how the line runs down.
Lay your hidden staging beneath your layout in the app and see straight away whether the gradient and the clearance work.
