Autodesk Inventor has a roller chain design accelerator that can produce quite complicated chains. So half an hour of playing around and I’ve managed to make my chains ‘properly’.
Only problem is that it doesn’t actually show the ‘chains’ just where they should be 🙁 I guess it would complain with several hundred extra parts…
It’s also perhaps possible to create a new chain type, with my rollers, as a standard component, but if I can’t even see them there is no point….
It’s not a complete loss, it will tell me how long each should be and allow me to change the size of each sprocket without too much messing around. The model also has a HUGE 1.4m invisible roller at the top ‘pushing’ the chain down.