Hello Everyone,

First some background, I'm an engineer with CNC machining experience and GD&T. I have a machine shop and have been thinking about building a CNC router capable of cutting aluminum and wood to within 0.001" repeat ability.I have been researching many sites with many DIY kits and DIY from scratch builds. No one seems to talk about how accurate and repeatable their machines are. From my experience, one cannot simply bolt some extrusions or steel tubing together and get the assembly to be planar within a 0.001". Do you build a flat reference surface/table first, then assemble? Does anyone use the old tight wire technique to ensure their rails and trucks are fastened to the metal base without dips or sags? Please give me some insight on how you are building a CNC router in three axis with precision.