This is an improvised passenger car for the OS-Railway system, and especially for the Hectorrail 141. It's not a scale car, although it is made to look like older passenger cars used on the Swedish railway network. The length is particularly important for this system as the track radius is very tight.
The car is designed to be printed on the Prusa i3 where the longst part, the body center section can be printed at 54 degrees Z-rotation.
Main track page: https://www.thingiverse.com/thing:2146361
Hectorrail locomotive: https://www.thingiverse.com/thing:2575667
Z70 locomotive: https://www.thingiverse.com/thing:2146425
(The RC6 cannot tow this car, it's too long and these are not the same scale).
8pcs ball bearings OD 6mm ID 3mm T 2,5mm
4pcs wheel shaft, carbon fiber 3mm thickness 42mm length
M2 screws (or most parts can be glued). However, I recommend that the boogie sides are screwed in place so that you can remove them if the bearings needs to be cleaned or adjusted. Buy long ones (around 20mm) and cut to length, the length is not critical.
2pcs M3x6 to attach the boogies to the car, this length is important if you want the screws to be hidden under the floor.
4pcs M3x8 attaches the boogie frame to the hub (2pcs for each boogie)
2pcs M3x10 for couplers
The roof guid plate does not have a built in tolerance to the body sides as this can vary due to print quality. You will probably need to trim the edges until it fits easy inside the small edges on the body. Its purpose is to hold the roof i place together with the lock pieces.
The cover plate for the light cutout in the roof can be printed if you have a semi-transparent material.
In order to simplify the printing process, use the prepared build plates numbered 1 - 9. They are designed to be in the order where the same color is likely to be used, for example body parts and doors in the same color. All the individual parts are also included if needed, se attached zip-files.
Wheels can preferably be printed in two colors, the last layer (or layers) in a bright color which greatly improves the visibility and ease of placing it on the track.
An attached picture shows the intended routing of cables for LED's although no LEDs are installed in the prototype at the moment of publishing.
Seats are included but not installed in the prototype. If you have a multicolor printer you can combine the seat frame and the seat insert, otherwise use the included build plate STL's and use CA (superglue) to glue them together.
The car easily becomes top-heavy due to the roof pieces. If going too fast in the sharp turn radius they easily topples over. In order to avoid this, weights should be mounted on the underside of the chassis to increase stability. Search for car wheel balancing weights. They are perfect for this as they normally come with double side tape.
Door is designed to be installed without any screws or extra hardware. The edge closest to the hinges needs to be sanded until the door can move freely.
This video shows the reason for the specially prepared roof STL. This orientation and the thin walls connecting the parts ensure that they can be printed vertically which gives the best surface. In this orientation, even a 0,25mm layer height will give good result. Part in picture printed at 0,2mm layer height.