This is my very first CNC machine. It measures about 5' x 4'. The z-axis is about 3.5 to 4 feet high. I originally designed the bottom frame for a 2.5 feet width, but decided to make it 4' (which is the reason why it looks funny). I used mild steel and did all the welding myself since the advice I got was to make it as rigid as possible. I am using THK rails/bearings for the X & Y axis. Any suggestions is appreciated.