I began working on the wheel assemblies as I believe them to be one of the primary assemblies of the project, since the wheel bogies are what hold the coaster to the track. I know that each bogie would have to have 6 wheels--2 road wheels, 2 guide wheels, and 2 upstop wheels-- so I began by creating reference shapes (the final wheel design will be once bearings are ordered). I worked backwards to create the frame, first designing the plates that must sandwich the wheels, then connecting them after. This guaranteed that the most important geometry be modelled first and can easily be changed without future sketches coming back with errors over minor differences
I also wanted to minimize cost, so I tried to use materials I had in easy access unlike some bolts or screws. This led me to use staples and bent paperclips as axles for the wheels. I was genuinely surprised at how well they work, so I decided to keep them. However, they can be difficult to put in place so it may be subject to change in order to expedite assembly time later on when there are a larger number of bogies that need to be completed. I also do not know quite yet how I will add support to the other side of the road wheels and upstop wheels. I currently have a plate that is a separate part due to printing constraints, and the paperclips are holding it in place, but I know that will not be able to hold the full weight of a moving train on constantly turning track. I believe I may have to use bolts, but at this scale I will have to carefully select what sizes.
This image shows the first fully assembled bogie (right) with the first tests at connecting the separate plates (left) in comparison to the tip of a #2 pencil to get a sense of scale
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