Well I have decided to build a cnc machine now what? I plan to use Mach 2 or 3 software to control it. I would like to build a small say 2'x2'x6" to start but I want to be able to do wood and metal ( metal to make parts for bigger system in future) I will be doing 3 axis for now 4,5,6 with bigger machine. So the big question is what size motors what motor controlers Plans and a material list? I really dont get how the threaded rod is suspended and driven backlash and loaded nuts etc.. Could someone explain the construction of a nice cheap gantry system with pics for the Newbie PLEASE. I want accuracy at a fair level I really dont know what is considered good in accuracy .001 is what I would like to get or better.

Thank You
Berry

Read through the FAQ section, for starters. Then keep reading through as many threads as possible, and do some searches. Read through some of the build threads to get an understanding of what youre in for.

Firstly...if you're thinking of using threaded rod....throw out the 0.001.....if you're looking at the jrgo design....you can probably also chuck the 0.001 (I'm sure those that have built the jrgo design will chime in)....if you want to get anywhere close to 0.001.....think linear rails (not linear bearings)....think 25, 30, or 45 for size of each linear rail on each axis....then think cast aluminum jig plate of 0.75 to 1 inch for all the major pieces....except where you might be able to use 80/20 extrusions (which should be at a minimum 2040 heavy extrusions....better if you use even wider ones...). Also ballscrews....most likely ground......well if you have or want to buy heftier servos or steppers....ACME screws will work.

Okay, which category do you wish to play in??