I've done plenty of research into these machines and gone back and forth as to what type of design to use as the basis for this model. I like the older style machines where the whole cylindrical section actually rolls, as opposed to rotates. While this would look cool, there is too much chance for error while operating. The more modern rotary dumpers would be easier to engineer, but the operation of the machine would still be dependent on the proper meshing of the large ring gear. While leafing through that latest Bethlehem Steel book I came across a few dumpers, one of them, for coal, struck me as a good prototype to model, abet, for ore not coal. This dumper, pictured below, has a car cradle that pivots on fixed trunnions and would certainly be more likely to not malfunction.
|Machine at Bethlehem Steel|
|Sketching it out - working out the geometry|