How to Change a Dry Wall Corner to Round

Measure the length of the area where the corner bead will be applied with a measuring tape. If necessary, cut lengths of corner bead to fit with tin snips. Vinyl corner bead is less apt to show cracks than metal corner bead and is easier to cut.

Set the corner beads in place and attach them to wall studs with drywall screws. Alternatively, lightly spray the inside of the corner bead with spray adhesive before applying it to the wall. If applying corner bead to the top of a wall, be sure that the corner bead is tight against the ceiling.

Mix the joint compound well so it is smooth and easily spreadable. The mixture should have the consistency of cake frosting so it can flow into the holes into the corner bead and lie smoothly against the wall. If the joint compound is too stiff, add a small amount of water to the mix.

Coat the corner bead with joint compound, working it into the holes and smoothing it along the length of the corner bead with the drywall knife or drywall smoothing tool. Avoid applying the joint compound too thickly. Two to three thin coats creates a cleaner, smoother appearance than one thick coat.

Allow the joint compound to dry for the time recommended by the manufacturer. Apply a second coat of joint compound and allow it to dry.

Put on a respirator. Sand the area until smooth.