I agree that you should definatly get on and build it, probably learn more in the process. good luck.

May have retract my statement about cable stretch being low...
Had a look around today and seems that 1m of 3mm dia. stainless cable will stretch 0.5mm under a 200N load (20Kg ,not much if cuting Al and a heavy gantry)....:geek:

May be start a new tread If anyone is intested in following this topic up? Im not used to designing things that move! traditional to keep structures stationary. There must be a way to get cheap and accurate control of CNC machines........