Need Help moving 48x48 inch printbed

[Phinieo]

Hiya All,I'm making a large 3D printer but I'm having issues moving the printbed. My current goal is to have a ballscrew on each side with a 1A stepper driving each of them. Ill offset the weight with some constant force springs pulling it up. My trouble is powering all 4 of the 1A steppers off of a single motor driver. I'm using a smoothieboard and only have room left for one more stepper driver which I would hope wouldn't be a problem given all of their inputs should be the same. So how should I power 4 1A steppers off of a single stepper wired to my smoothieboard? I would very much appreciate suggestions for a sufficiently powerful driver as well as wiring ideas.Thanks!