Thanks for posting this. I am in the process of ordering parts for a new D-Bot build pretty much identical to yours. I have a quick noob question; On the 3-lead screw mod, what GT2 pulleys do I need to achieve the 1:1 ratio for screws and motor? I've ordered these 8/2 lead screws: https://www.amazon.com/gp/product/B017AR5QBS/ref=od_aui_detailpages01?ie=UTF8&psc=1 and these stepper motors: https://www.amazon.com/gp/product/B06ZY9SPWL/ref=od_aui_detailpages01?ie=UTF8&psc=1. Im just new at this and am unsure about the pulleys as there are so many choices.