The LTM Series 21-35 consisted of 15 standard gauge steam locomotives, built between 1922 and 1925. They where built by Hanomag, and used by the Limburgsche Tramweg-Maatschappij on varius tram routes in Limburg (NL). One of these engines was preserved, and can still be seen in operation at the Hoorn-Medemblik heritage railway.
The LEGO® model is built in 1:45 scale, and can be motorised with an 9v, PF, or PU train motor. There is no room for a battery box in the loco, but there is space to route the cable out trough the back of the cab to connect to an external battery box in a wagon.
The Netherlands isn’t particularly famous for its steep terrain, but in the south of Limburg there are some hills to be found. To overcome them, the Limburgsche Tramweg-Maatschappij ordered one of these articulated Garratt locomotives from Henschel. It was delivered in 1931 and was the the only Garratt locomotive to operate in The Netherlands.
Similar to other LTM locomotives, the Verhoop valve gear was internal. The watertanks for the engine where located on the outside of the frames, under the footplates.
The locomotive seems to have been a succes, I couldn’t find any evidence of serious issues or extensive repairs having to be made. Despite this, the locomotive was retired after only 7 years in service. By this time the road infrastructure in the area has improved, and in 1938 the LTM stopped operating trams on the line Maastricht – Vaals, where this locomotive was designed to run. The locomotive was apparently sold to a buyer in Germany, and has since disappeared.
The lego version is modeled in approximately 1:45 scale, and is powered by two 9v train motors. It should be possible to replace the old 9v motors with RC train motors, but you would need to find a place to put a the battery pack.
The cab roof is removable to reveal a simple interior. The loco is designed to work on standard R40 curves & switches, only the 2 pieces of flex tube between the front bogie & main frame prevent the model from ruining on tight curves, and can easily be removed if needed.
The technique for the smoke exhaust comes from Farouq (https://flic.kr/p/2kGn2dW) and is made using the internal part of a LEGO technic shock absorber.