Power Ramps thru arduino input connector? (1 reply)

Hi everyone!
I have a Ramps 1.4 And arduino mega with LCD screen. the Ramos board is only going to control three steppers for a cnc machine. I was wondering if I could just plug my 12v power supply into the arduino to power the ramps and steppers? Instead of cutting the end off my power supply and plugging into the ramps input terminals.

Thanks,
Mark