How to Cut a Square Hole in a Metal Door

Place a screwdriver underneath the hinge pin and tap it with the mallet or hammer to move the hinge pin out of place. Repeat for each pin. Have a helper balance the door, so it doesn't fall.

Lay the metal door across two sawhorses or on top of a sturdy worktable.

Measure and mark the placement on the door. Draw the square shape for the window or pet door onto the door, using the marker and the straightedge. If the door or window comes with a template, trace around it.

Put strips of low-tack masking tape up to the marker line to protect the surface of the door from scratches.

Put on the face shield or safety goggles and work gloves.

Equip a power drill with a 3/8-inch titanium bit. Position the drill on the inside corner of the square and drill through the door. Repeat for the remaining three corners.

Install a carbide blade into a jigsaw. Insert the blade into the hole and cut along the guideline to the hole in the next corner. Turn the saw off and turn it 90 degrees. Cut along the guideline to the next hole, shut off the saw, turn it 90 degrees and cut along the line to the third hole. Turn off the saw, turn it 90 degrees and cut along the final line.

Rub a cross file along the edges of the hole to remove burrs and slightly dull the sharp edge.