@gisli said in Moving mass / torque requirements:
@deckingman Ian, your setup is very interesting, I have never seen counterweights used in this way,
Forget the counter weight / dynamic load balancing thing - it makes no difference (although it might if the frame flexed rather than the entire printer "rocking"). The point was that you can print at 300mm/sec (if your hot end can melt filament that fast) with a mass of 1.5kgs using Nema 17s.
I don't know of any long, thin, nozzles that would accomplish what you want to do.
6mm belts will be fine - it's what I use. Timing belts are designed not to stretch (although some cheap Chinese ones might).