cnc

[natchez]

how long of a rod can i use before i have to support it

[Splint]

More information please. Are you talking to support the whole gantry, if so how much might it wiegh. How much rigidity do you require and what size rod (diameter) do you expect to use. Without this info we dont know if you're planning a desktop router or a 5' by 10' machine. The more information you can give the better.

[natchez]

i have some thompson three quarter rod and pillow blocks they are 24 inches long i was wondering if i could build a cnc out of them i want use them on the x and y axis

[Splint]

I'm confident it will work ok over 24 inches. If worst comes to worst you could make supports which would be mounted to the part of the rod diameter which is disused (between two of the three bearings which the gantry will run on) but I dont think you'll have any problems.