An apparatus for repairing a metal sheet and method of operating the same are provided. The apparatus includes: a base unit including: a frame and an attachment feature on the frame, a cutting unit removably attachable to the base unit to cut out a damaged portion of the metal sheet, and a welding unit removably attachable to the base unit. The cutting unit includes: a cutting arm including a cutting blade, and a motor for operating the cutting arm. The welding unit includes: a fixed platform, a weld movement motor for moving a moveable platform on the fixed platform, and a welding assembly, attached to the moveable platform, to automatically weld a replacement piece to the metal sheet. In operation, the frame is continuously attached to the metal sheet during cutting of the damaged portion and welding of the replacement piece, providing a stable and repeatable frame of reference.