The norm

The H0 railroaders have finescale standards such as H0-Pur, Proto: 87 or FREMO:87. It is called N-Bahners fiNstop. In TT, the finescale concept has unfortunately not yet progressed very far. There was always a single effort in TT to rethink the wheel-rail system, such as Thomas Meinhold on his side Fine modules shows, but his idea could not mature due to lack of time and interest of others. The main reason of disinterest is surely the incompatibility too NEM 110 Tracks and NEM 310 Wheelsets.

In the following, less of a finished standard will be presented, no, it should rather be seen as a proposal for a finescale standard for era I and early era II.

The wheel-rail system

Chassis and wheelset

Inner distance between side members: 15,47 mm
Inner spacing of axle holder: 15,07 mm
Axle bracket plate thickness: 0,20 mm
Inner distance axle bearing: 15,47 mm
Inner distance bore axle bearing: 16,51 mm

Axle length of the locomotive (flat): 14,3 mm
Axle length carriage (pointed): 16,50 mm
Axle diameter: 1,50 mm

Wheel set inside dimension: 11,18 mm
Outer wheel dimension: 13,78 mm

Wheel width: 1,3 mm (1,1 mm possible)
Flange height: 0,5 mm (0,3 mm possible depending on the model)

About the British 2mm scale association can be 1,3 mm wide rim with a diameter of 6 mm - 14 mm. 8 and 8,5 mm can be used for state railroad cars. Membership is required to place an order, which is reasonably priced at £ 27- £ 31.

The axle bearings mounted on the 0,2 mm thick etched nickel silver axle holders are made in brass investment casting or 3D printing. It is also possible to create the complete undercarriage with axle bracket, bearings and suspension as a unit in 3D printing.

The wheel stars for locomotives and cars in 3D printing.

Sleepers

The TT FineScale track consists of lasered real wood sleepers, printed or cast base plates and Code40 rail profiles. The track described is the 3rd order superstructure from 1892 of the RSSR. The values ​​in brackets are the original values.

sleeper length: 20,83 mm (2500 mm)
sleeper length joint: 22,50 mm (2700 mm)
sleeper width: 2,00 mm
sleeper height: 1,50 mm
sleeper distance: 6,5 mm (7800 mm)
sleeper distance joint: 4,5 mm (540 mm)

base plates

The development of the Saxon base plates for the 3rd order superstructure has not yet been completed. On the one hand, there are still slight adjustments to the dimensions to guarantee simple threading and at the same time a firm fit of the Code40 profile, and on the other hand there is still a test regarding the material and the production. So far, 3D printing in stainless steel has been very promising (Select Laser Melting (SLM)). Furthermore, base plates in 3D reprint (MSLA) with a PRUSA SL1, as Investment casting in brass be tested. When it came to construction, I got inspired by Klaus-Dieter Pfennig and his Prussian base plates in H0Pur . What is difficult in H0 is definitely at the limit TT-scale.

…to be continued…