Sectional track or flexible track: which should you choose?
Benjamin | TrackDrawer.com · published 8 November 2026
Choose sectional track if you want to build quickly, take the layout down again or are not yet sure how it should look: every piece has a fixed size and everything fits together. Choose flexible track for a permanent layout where you want long, flowing lines with fewer joints and curves of any radius. Most permanent layouts use both: sectional track and turnouts in stations and junctions, flexible track on the open line in between.
What the difference is
A piece of sectional track has a fixed shape: straight at a given length, or curved with a fixed radius and angle. A sectional system is designed so the pieces close up. Twelve 30 degree curves make a circle, and a turnout plus its matching curve put a second track exactly at the track spacing.
Flexible track is a long length of track whose sleepers can move relative to each other. You bend it into the shape you want and cut off the excess. You choose the radius, and the length too. The catch is that the track only keeps its shape once you fix it down.
Which systems offer flexible track
Not every track system has flex track. In our catalogue nearly half of the systems have one (15 of 32), usually a length of about 0.9 m in H0 and 0.7 to 0.8 m in N.
| System | Flexible track | Length |
|---|---|---|
| Roco Line | 42400 and 42401 | 920 mm |
| Piko A-Gleis | 55209 | 940 mm |
| Märklin K track | 2205 | 900 mm |
| Fleischmann Profi-Gleis | 6106 | 800 mm |
| Tillig Elite | 85125 | 890 mm |
| Peco Streamline OO/H0 | SL-100 and SL-100F | 914 mm |
| Minitrix | 14901 | 730 mm |
| Fleischmann piccolo | 9106 | 777 mm |
| Märklin Z | 8594 | 660 mm |
Our catalogue has no flex track for, among others, Märklin C track, Trix C track, Märklin M track, Roco geoLine, Kato Unitrack H0 and Hornby. These are systems designed for quick assembly, often with a fixed roadbed. If you want free shapes with Märklin C track, you often mix in a section of K track: read more in C track or K track.
Peco Streamline is the opposite: in our catalogue it consists only of flexible track, turnouts and crossings, with no fixed curves. That is why the Auto-designer does not lay fixed plans with it; you draw them yourself.
Why sectional track
- Predictable. Every piece has a size from the catalogue. A plan on paper or in TrackDrawer matches what you put on the table.
- Fast and reusable. You click a layout together in an afternoon and take it apart later. Ideal for the floor, around the Christmas tree or for a layout that is still growing.
- No tools. Sawing, filing and fixing are not needed, except perhaps a few screws to stop it sliding.
- Turnouts line up by themselves. The fixed turnout geometry makes sure a passing loop ends up at the right distance. How that works is explained in track spacing.
The drawback: you are tied to the radii the system offers. In Roco Line, for example, the curves are 358, 419.6, 481.2, 542.8 and 604.4 mm. If you want 500 mm, that piece does not exist.
Why flexible track
Fewer joints. Every joint is a spot where the train can feel a bump and where current has to pass through a rail joiner. A 2.76 m straight in Roco Line is 12 straight G1 pieces of 230 mm, with 11 joints in between. With F4 flexible track of 920 mm it is 3 lengths and 2 joints.
Any radius. You bend a 500 mm curve if you have the room, or a sweeping curve that just clears a chimney breast. Fixed pieces do not allow that.
Transition curves. A real railway does not go from straight to the full curve in one step. With flex track you let the radius tighten gradually. Trains enter more smoothly and a long coach swings out less abruptly.
A prototypical look. Long, gently curving lines look like a real railway. A layout built from sectional track often gives itself away with its circular curves.
What flexible track asks of you
- A solid baseboard. Flex track only holds its shape once you fix it: pin, screw or glue it to the board or to a cork underlay.
- Cutting and filing. In a curve the inner rail slides further than the outer one. After bending, cut both rails to the same length and file off the burr.
- Care at the joints. A joint in the middle of a curve easily causes a kink. Put the joint on a straight if you can, or solder two lengths together before you bend them.
- Planning. Because the shape is free, it is up to you to make sure a curve does not get tighter than your rolling stock can handle. Check the minimum radius the maker of your locomotive and coaches specifies.
Combining both
In practice few people choose one or the other. Turnouts, crossings and the first metres of a station are always fixed pieces, even in a flexible track system. In between you lay flex track.
A common approach:
- Lay the fixed parts first: stations, turnout ladders and junctions.
- Connect them with flexible track, using curves as wide as possible.
- Use short fixed pieces where flex track is too short or too stiff, for example right behind a turnout.
Still have a box of old sectional track? It usually works well in the fixed parts or in a fiddle yard. Read giving your old box of track a second life.
Frequently asked questions
Can flexible track be bent tighter than the smallest fixed curve?
Technically it often works, but it is rarely a good idea. The smallest fixed curve of a system is already a compromise for small layouts. With flex track, stay above the radius your rolling stock can handle, and preferably well above it.
Can I simply join flexible track to sectional track?
Within one system, yes: the flex track of Roco Line, Piko A-Gleis or Märklin K track is made to join the fixed pieces of that same system, with the same rail joiners. Between different brands or rail heights you need a transition track.
In TrackDrawer
In TrackDrawer you can bend flexible track towards a target: the app looks for a shape with the largest possible radius within the length of your piece. The gap closer searches your stock for the fixed pieces that close a gap exactly. Enter your track and let the Auto-designer suggest a plan; then replace any run of fixed pieces with flexible track where you like.
