Builder: Sven J.
About Swedish Class S1 2-6-4T in 1/32.5 scale by Sven J.
The prototype:
From the 1920s on already, the Swedish State Railways (Statens Järnvägar, SJ) pushed ahead with the electrification of their route network. Nevertheless, a few steam locomotives were also procured after the Second World War: After ten 4-8-0 locomotives (class E10) had already been put into service in 1946 and 1947, twenty units of the S1 series followed in 1952/53. These elegant 2-6-4 tank locomotives were primarily intended for use on branch lines that were not due for electrification, in order to bridge the time until reliable diesel locomotives or railcars arrived. In accordance with this purpose, the locomotives were designed with an exceptionally low axle load of only 12.6 t, despite their overall quite impressive size (only slightly smaller than the German class 64 in all relevant parameters). When only the rear tank was filled, the axle load could be reduced even further to just 11.5 t.
All engines were built by "Nydqvist & Holm AB" (NOHAB) in Trollhättan and classified by the SJ as road numbers 1910 to 1929.
Being the last steam locomotive class developed and built for the SJ, the S1 had some modern design features, such as the welded construction of the boiler and roller bearings for all axles. Overall, however, the locomotives were of a rather conservative design and were ultimately already outdated when they were delivered, as many other components were carried over from older classes.
The model:
My model was finished in July 2022. It is held in exact 1/32.5 scale, consists of approx. 2,400 parts and weighs around 1.4 kg. The locomotive is driven by two vertically-mounted PF-L motors, which are directly connected to the 2nd and 3. coupled axle; the 1st coupled axle is driven by the rods.
A BuWizz 2.0 is used for power supply and remote control. Lighting equipment (directional headlights and cab light) is from Brickstuff, while the wheels were purchased from BBB. The rods and valve gear parts are 3D printed elements of my own design.
Here's a video: https://flickr.com/photos/183011768@N06/52619238756/in/album-72157716546323673/