I should have put something there as you said,to give a sense of scale.If it is of interest I could re assemble it by a ruler (its been`off the wire`for a while now,but doesn`t take long to hang it up.Anyway,to give an idea of scale in the meantime,the sheeve wheels are 4inches in diameter each.The main `frames` are 6mm thick mild steel,the `axles` are 16mm diameter mild steel bar (drilled centrally 6mm for the fixings to lock the plates togethe`).The main frames are drilled 16mm to hold the weight of the things,whilst the outer fixings hold the assemblys together.As I said its a little overbuilt compared to the full size things (the main plates only act as a spacer for the strapping which takes all the weight-the four sided plates only hold the strapping to the required gradient)but I wanted it to look proportionally the same,and also to be capable of work safely if required.The pulleys (unfortunately solid not spoked) were from a lifting gear place.
Hope this helps to give some idea,let me know if I should put a clearer photo up(from the side?).