Compact System Geometry
Coordinated straights, curves and turnouts simplify small stations and multi-track routes.
ROCO TT Two-Rail Track Without Roadbed
ROCO TT Track
An illustrated overview of the ROCO TT track products verified at Modellbahnshop: short straights, the standard straight, 640-millimetre flexible track, R1 and R2 curves, standard and curved turnouts, a double-slip turnout, electric and concealed turnout drives, connection and isolation accessories and selected layout track sets.
TT gauge
1:120 scale
12 mm track gauge
1.8 mm rail profile
two-rail operation
without roadbed
Verified range as of:
Compact TT Track System for a Custom Roadbed
What is the ROCO TT track system?
The ROCO TT track system is a two-rail track system without a permanently integrated ballast roadbed. Rails and sleepers are laid on a prepared route and then individually secured and ballasted.
The system belongs to TT gauge at a scale of 1:120. The model track gauge is 12 millimetres. The rail profiles are 1.8 millimetres high.
The 128.7-millimetre G128 straight forms the standard length. G64 is half this length. Straight G121 is used, among other things, for geometric compensation with standard turnouts and the double-slip turnout.
The 640-millimetre G640 flexible track permits free radii, transition curves and individually cut route sections.
The fixed curved track uses R1 with a radius of 321 millimetres and R2 with a radius of 365 millimetres. Depending on the product, angles of 10, 20 or 30 degrees are available.
Flexible Track for Freely Planned Routes
G640 permits transition curves, individual radii and flowing track alignments.
Retrofittable Turnout Drives
The integrated snap mechanism permits manual operation first and motorisation later.
Straights, Radii and 20-Degree Turnout Geometry
Compare ROCO TT Track Geometry
Twelve curved sections of 30 degrees each form a complete circle. The 10- and 20-degree curves provide geometric compensation and turnout connections.
| Track Element | Length or Radius | Angle | Product | Typical Application |
|---|---|---|---|---|
| G44 | 44 mm | – | 4080100 | Short length compensation |
| G60 | 60.5 mm | – | 4080101 | Half the length of G121 |
| G64 | 64.3 mm | – | 4080102 | Half the standard G128 straight |
| G121 | 120.96 mm | – | 4080103 | Compensation for turnouts and the DKW |
| G128 | 128.7 mm | – | 4080104 | Standard straight and basic grid |
| G640 Flexible Track | 640 mm | Free | 4080105 | Free radii and transition curves |
| R1 | 321 mm | 10° or 30° | 4080110, 4080130 | Compact inner circle |
| R2 | 365 mm | 10°, 20° or 30° | 4080210, 4080220, 4080230 | Outer circle and turnout geometry |
| WL20 / WR20 | 128.7 mm / R 365 mm | 20° | 4080420, 4080421 | Stations and sidings |
| Curved Turnout | R1 321 mm | Curved route | 4080460, 4080461 | Junction within a curved route |
| DKW20 | 128.7 mm / R 365 mm | 20° | 4080800 | Compact double track connection |
Check the Vehicle Radius
Long coaches and larger locomotives benefit from R2 or even more generous flexible-track radii.
Use the Connection Terminal Correctly
For digital operation, the interference-suppression capacitor in connection terminal 4081710 must be removed.
Plan the Substructure and Roadbed
The route, sound insulation, fastening and ballasting are constructed separately to suit the layout.
Verified Modellbahnshop Products Only
ROCO TT Track by Product Group
Every product card links directly to the relevant product page at modellbahnshop.de. Search terms can include “4080104”, “flexible track”, “R2”, “WL20”, “DKW”, “connection terminal”, “buffer stop” or “Hohenstein”.
No manufacturer pages, third-party retailers,
automatically generated product links or images of
similar replacement products are used.
No verified ROCO TT product matches this search.
From the Track Plan to a Reliable TT Layout
Planning and Laying ROCO TT Track Correctly
Radii, flexible track, turnout drives, power feeds, feedback sections and subsequent ballasting should be planned together.
Compact Station
G128, G121, 20-degree turnouts and the DKW permit space-saving station tracks.
Visible Main Line
Flexible track permits larger radii and smooth transition curves.
Modular and Sectional Layout
The clearly defined system lengths simplify track transitions at section edges.
Step 1
Match Vehicles and Radii
Check the minimum radius of the longest locomotives, coaches and multiple units.
Step 2
Define the Track Grid and Flexible Sections
Fixed track and freely shaped route sections should be clearly distinguished in the track plan.
Step 3
Plan the Electrics and Drives
Power feeds, isolation points and turnout drives should be marked before the track is secured.
Step 4
Test First, Then Add Ballast
Test every route using different vehicles before completing the final scenery.
Avoid Common ROCO TT Track-Construction Errors
- Using R1 without testing long vehicles
- Securing flexible track under tension in curves
- Confusing G121 and G128 in turnout formations
- Providing too few electrical power feeds
- Using the connection terminal unchanged on a digital layout
- Allowing ballast adhesive to enter turnout mechanisms
Guidance About the Double-Slip Turnout
For electric operation, the DKW20 requires two suitable side-mounted drives or two underfloor drives.
Answers About Geometry, Flexible Track and Turnouts
Frequently Asked Questions About ROCO TT Track
Answers about scale, track gauge, straights, radii, turnouts, drives, the connection terminal and track sets.
What scale does ROCO TT use?
TT gauge uses a scale of 1:120.
What track gauge does the track use?
The model track gauge is 12 millimetres.
Does the track include an integrated roadbed?
No. The ballast bed and sound insulation are constructed separately.
How high is the rail profile?
ROCO TT track has a rail-profile height of 1.8 millimetres.
How long is the standard G128 straight?
Product 4080104 is 128.7 millimetres long.
What is straight G121 used for?
G121 is 120.96 millimetres long and is used, among other things, as a compensation straight for standard turnouts and the double-slip turnout.
How long is G640 flexible track?
Product 4080105 is 640 millimetres long.
Which fixed radii are available?
R1 has a radius of 321 millimetres and R2 has a radius of 365 millimetres.
How many 30-degree curves form a circle?
Twelve curved track sections of 30 degrees each form a complete circle.
What geometry do WL20 and WR20 use?
The turnouts are 128.7 millimetres long, have a diverging angle of 20 degrees and a diverging radius of 365 millimetres.
Which curved turnouts are available?
Product 4080460 is the left-hand curved turnout and product 4080461 is the right-hand version.
What geometry does the DKW20 use?
The double-slip turnout is 128.7 millimetres long, has a crossing angle of 20 degrees and a diverging radius of 365 millimetres.
Which turnout drives can be used?
Product 32418 is available for left-hand turnouts and product 32419 for right-hand turnouts. Underfloor drive 10030 can be used as an alternative.
Is the connection terminal suitable for digital operation?
Yes, after the integrated interference-suppression capacitor has been removed. The capacitor remains installed for analogue operation.
Which layout track sets are included?
The overview includes Hohenstein, Thierstein, Karlsberg, Neumannsee, Hohenwiehl and St. Florian.
Further Modellbahnshop Sections
Related Topics for Your TT Layout
ROCO Manufacturer Range
Discover vehicles, track and accessories.
Straight and Curved Track
Compare further TT track systems.
Turnouts
Select further turnout designs.
Track Accessories
Add drives, joiners and electrical equipment.
Track Sets
Discover complete packages for layout plans.
Compare Track Systems
Understand track gauge, rail-profile height and roadbed.
Plan a Model Railway
Define the area, radii, station and electrics.
Model Railway Guide
Basic guidance about track construction and layout planning.
From G128 Track to a Complete TT Layout
Plan radii, flexible track, turnout drives, power feeds and maintenance access together.