Well I'll give this a stab - this is how I described it to my girlfriend and why she hasn't seen hide nor hair of me for the last three months - it's kind of like driving a car sweetheart - I did the research on new units and thougth they were "too expensive", came up with my own design researched the parts, put the mechanical parts of the table together, that was easy, built the controll box : stepper controll board, parallel port breakout board, stepper board power supply, breakout board power supply, shielded cable to the motors, geared stepper motors, Campbell THC300 torch height controll, connected that to the plasma torch put all that together, put together a clean dry air supply, bought a computer and coreldraw,sheetcam,mach2/3, learning that not easy at all, designed a floating head Z-axis for the THC300, and am just now getting ready to test everything and see if it will work together - yes honey I just got in the car and started the engine and I think there is more to this driving than meets the eye, excuse me while I design and build this differental and mount it while i'm at it! Other things to think about - home and limit switches, radio noise interfearence, 230 volt power, oil vapor free air, swarf and dust, the cost of metal and finally your own sanity! You got to really love DIY to do this and be ready to do a lot of research and ask questions. I now think the ready made machines aren't such a bad deal after all. Good luck.