I am going to build a CNC 4x4 plasma table. The frame is made of 1 1/4" pipe and the gantry will be made of either 2"x 2" or 2"x 3" tubing. What size stepper motors do you suggest?

We recommend our electronics combo for the scratch build kit, which you can find on our site here: https://buildyourcnc.com/item/electronicsAndMotors-3axis-425-elcombo. This is our standard general purpose 3 axis electronics system, and includes (3) NEMA 24 425 oz-in stepping motors, (3) Drivers (3.0Amp 24-40 Volts, with 1-1/64 microstepping), (1) 36v 8.8a Power Supply, (1) Interface Board either USB or Parallel. (The USB version requires PlanetCNC software; the parallel interface board gives you a variety of options, Mach3 being one popular choice.)