More coaches from the 3D printer.

The international coach I1

Developing the I1 is fully similar to the M1 coaches. With consultation of a drawing of H. de Bleser, knowledge of the nominal size of windows and rivetted strips and viewing the rare photo's on internet etc. a 3D drawing can be made. Of course also here there are some learning points which require modifications in the printing process to obtain a better result, but the first print already made it into a running example for some test runs on a Fremo meeting, albeit with still failing items such as battery boxes, steps etc. It concerns the regular I1 series steel coach from early thirties for international traffic as first/second class. These differ slightly from the 10 prototype coaches in height of the coach side and the ends. This is visible as a step in the lower edge between door and coach side.

There were also newer coaches to the same base drawing built after WW2 as welded construction, the I2's, thus no rivets and no strips, here the door hinges are on the outer sides with two handrails. But the windows were modernised too and have a rectangular surround in aluminium colour. This probably requires window frames and glass to be produced apart, such that these can be painted separate and inserted into the coach side as a unit. This approach requires some experiments first, but these are also necessary for production of other coaches that were either upgraded with new windows or newly built with such. Such window frames definitely complicate production, I will first concentrate on the low hanging fruit to make steps.

Images with the 11 seem to be extremely rare on internet. The above shows one, probably in new condition, somewhere half in the 1930's, most likely an original NMBS photograph with the new logo in the lower left corner. The colour seems to be the dark blue/khakyish-beige livery with a greyish-black roof and with the center rivet strip in black, the CFB-BSM logo was replaced by the B logo halfway the 1930's.

This is my first approach based on the drawing of H. de Bleser. Comparing it to the above photo shows that the roof ends should be drawn up a bit 'fuller'.

printed and painted result

Compared to the M1 the floor was positoned 0.5 mm higher to prevent having to mill spaces for the wheel flanges. Unfortunately this led to some dents in the sides because of unsufficiently supported lower edge. Thus on the adapted version the interior is a separate print with the coach having interior spacers similar to the Nohab to keep them straight and parallel during the printing and curing. The roof was printed separate as with the M1. The floor will be a likewise metal sheet, but this time with printed battery boxes and footboards from thin brass to be realised at some future date. Bogies are identical to the M1 Pennsylvania type with rollerbearings, but one bogie should get an axle driven generator, this is drawn-up, but waiting on a free ride with other items.

Collection of printed parts for the I1, second version. The interior is now a separate part, same as the roof. Shown are also 2 bogies in grey resin, these are identical to those for the M1.

The 2nd test print on top and below that the prepared base plates for frames, cut with quillotine and then conventionally treated with jewellers saw and file to required dimensions. With the object to reduce waste as much as possible the frame for the bagage coach was cut from a better fitting sheet of NS.

I made 3 because that fitted the available strip of material, thus maybe also print at least one 3rd class (2nd after 1955) coach with more windows in the sides, or try an I2 version of this without rivets, not everyone travels 1st class.

This is the I1 B11 made following the same procedure. Not perfect, it shows a bit of curve, probably due to having spend some time in sunlight while the sun peeked through the blinds not being fully closed. The windows are individually set-in which is a lot of work. A different design for a coach with rigid enough coach sides where the glazing can be put in place as a single set could be a follow-up for other coaches.

updates may follow...

The short bagage coach

The short bagage coach seems to have the same coach ends and roof cross section as the I1, but it is a bit shorter and has only some small windows (i.e. similar to the toilet sized ones) with a set of slidng doors like the door in the M1 bagage compartment. Thus this coach forms a case of copy and paste from drawings already available.

This may become a cute little wagon in an international train.

first impression of RIC short bagagewagon
screendump of print ready bagagewagon with a fuller end roof
printed result

I1 second version and bagage coach painted and waiting for frame

The generator wagon

Of interest too are the generator wagons, which were rebuilts of short bagage wagons in later life for use with modern coaches with electric heating behind green diesels equiped with only steam heating.
Locating a drawing in my undocumented archive took some time. I found the information in TSP "op de baan" #70. These generator wagons were rebuilts from a different series of bagage wagons with the look-out in the center of the roof, similar windows and doors but in different position and the wagon is about half a meter shorter, they lack the rivetted strips and the heads are identical to the prototype I1's. Thus although they seem look-alikes they actually require a full new drawing. As generator wagon they loose their sliding doors on one side and the look-out is replaced by a longer upstand with 3 vents for cooling. A total of 7 were modified and used for international traffic North-South via Luxembourg. After 3 years in this traffic they were replaced by the blue 55's with onboard electric generator, there after they saw wider use in spurious trains with modern electric only coaches pulled by green/yellow diesels. Nice examples are trains to Lourdes in France with SNCF coaches and 2 class 60 loco's. Magazine "op de baan #70" shows mostly photos with 51's on front, but there also examples with 52, 54, 55, 59, 62 and CFL 18 (= red/yellow 55), thus plenty of believable choice for Fremo use.

Adapted drawing for the generatorwagon

The generatorwagon, not yet finished

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copyright: Henk Oversloot
date: 16 Dec 2022
update:Feb 2024