A couple of beginner questions... Profile sizes and cutting area size.

[Voicecoil]

The machine in the picture uses a single screw and as a cutting area of about 600 x 1000 if I recall correctly. However, I've built lots of machines with this design up to 700 x 1250 cutting area using single screws. If you wanted stronger machine at the same width/length say for cutting mostly aluminum or Hardwoods with heavy cuts then go with twin motors every time.

Nifty little machine that, I do like the integral control panel - might make something similar for mine if I have the time.