Ive been trying to get my mind around building a CNC machine, and looking at hardward and software, i'm not seeing where the measurement comes in. if( and i plan to) use MACH2 or if i can afford to buy it, MACH3, where does the position feedback come into it? it looks like there is not much I/O on the parallel port, so is positioning all done by step counting and math conversion based on the set-up and pitch of the leadscrews? if so, then i dont need any encoders or linear scales...right? or is there a way to integrate them?
thanks