Applying the rounded corners graduates the corner edge, moving from one wall to the next. Thus eliminating the sharp edges with a softening interstice.
Bullnose is available in right angle inside and outside beads, at 3/4″ and 1 1/2″ dimensions. The most common being the 3/4″. The 1 1/2″ can take a special order.
Poly bead is recommended over rigid metal-backed paper since it offers greater flexibility over the extruded piece and forms a corner that is less apt to show cracking with movements in the corners. Too, the vinyl corner gives an easier repair, which is simply done with a patch and not a cutout like from a deforming dent in the metal. By virtue of its shape, the rounded edge is ideal for taking impacts instead of the thin line edge on typical beads.
To apply the single corners:
1) Take either a pair of heavy scissors or utility kinfe and cut the length of the bead to fit. Typically they come in 8′, 9′, 10′ and 12′ sections.
2) Tack or screw the bead on in place. Some installers apply spray adhesive to the backside to hold the contour to the wallboard. A base adapter can be adjoined that will confors to the square edge of the baseboard which are mounted with adhesive, staples and/or nails.
3) Apply a coat of mudd which is thinned enough to infiltrate the bead surface openings. This will provide grab for the dried compound. Translating to greater durability and longevity of the corner surface.
4) When dry, run the knife edge over the surface to a flatter clean and reapply another mudd coat. If necessary, repeat this step a second time.
5) Sand off to a sufficient level.
For connected corners – horizontal to vertical, as in the case of an open doorway, snip the top and the adjoining piece at at mitre. Attach the strips at the corners and join with a molded connector.
Off angles, splayed at 120 degrees are a common dimension — which will have its own base adapter to fit.
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