EMD GP38/39-inspired freight locomotive for OS-Railway

thingiverse

This is a working fully 3D-printed freight locomotive for the OS-Railway project. Read more about the project here: http://depronized.com/2018/02/13/presenting-the-os-railway-system-fully-3d-printed-model-train-system/ This locomotive has an upgraded motor bogie capable of handling much bigger motors than previous designs. Instead of relying on an external gearbox, this design features a built-in 10:1 gear ratio, allowing you to operate it with a standard 380-size brushed or brushless motor. This means a diameter up to 28mm and the pinion has a 2.3mm bore but can be drilled up to 3mm without problem. Print without support, but make sure detect bridging is enabled. The grab rails are designed to be bent after printing. I think you'll see how it's supposed to be bent when you have the parts in front of you. Use drops of CA-glue to ensure the grab rail stays firmly attached. For electronics, see the Hectorrail 141 page: https://www.thingiverse.com/thing:2575667 This project requires the following hardware: Motor: 28mm DC-motor. Search eBay for lots of cheap 28mm DC-motors for RC-cars/boats. They usually have a 2.3mm shaft suitable for this gearbox. You can also use a brushless 28mm motor, but then you need to adapt the electronics accordingly. In that case, you can use a digital output on the NodeMCU to send a servo signal to a standard RC ESC. 4pcs 3mm thick 44mm long wheel shafts (carbon fiber works well) 1pcs 3mm thick 42mm connection shaft to make the motor bogie 4wd 2pcs 2mm or 3mm thick 16mm long shafts for the gearbox, either carbon fiber or steel Ball bearings 6mm OD 3mm ID 2.5mm thickness. SMR63ZZ ballbearings work well. You need at least 10pcs for the bogies and an additional 4pcs if you want to use ballbearings in the gearbox. Apart from the screws shown in the explode view, the following is needed: 8pcs M2x16 - 25 (for fastening the body on the chassis, or you can glue) For the forward bogie: 2pcs M3x12 1pcs M3x14 Use O-rings or small rubber bands on the driving wheels to ensure you get enough traction. If you want lights, there are 3mm holes for two lights in the front and two in the back. See schematic on the Hectorrail 141-page linked above. For further questions and discussions, please visit my forum: http://depronized.com/board/ Update 2020-08-11 - added a missing gear to the pre-assembled STL's of the motorized boogie. One of the two "Gear 11t wheel shaft gear" was missing, however present in the zip-file with individual parts so you don't need to re-print the whole boogie.