Hi I built a Rockliffe machine last year and it works great. Using 289oz/in stepper motors with 6mm x 1.0mm pitch allthread. It is much more accurate than I thought it would be within 0.0001mm. I set it up with Mach3 software and also purchased a C11 opto board from
www.cnc4pc.com they are great to deal with. My biggest problem now is I want a much bigger machine to do some grunty stuff on. I have found a guy in USA which has plans etc for a 1.2mtr x .66 mtr cnc router who has offered to email me the plans. If you are interested in a copy of them or a kit form let me know.
Cheers
Greg