How to Repair a Joint Compound Bulge in Drywall
- 1). Use your belt sander to remove the paint from the bulged area, and a few inches on either side of the bulged area.
- 2). Use your 6-inch putty knife to remove the dry plaster from the seam, scraping against the drywall from the top and bottom of the bulge. When you get under the drywall tape, scrape and pull it off, exposing the line between the two pieces of drywall.
- 3). Lay your mesh drywall tape over the seam, ripping it off at the end. Press it firmly to the drywall. Use your 6-inch knife to spread a thin line of joint compound over the tape, about 4 inches wide. Let it dry for several hours.
- 4). Run your hand-sander and sanding screen over the seam, smoothing out the compound. Use your 12-inch knife to lay a second, wider layer of compound over the first, making it about 8 inches wide. Let it dry, sand it down, then lay a third layer of about 10 inches wide. Let it dry and sand it down.
- 5). Re-paint the repair area to match the rest of the wall.
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