How to Mud Tape
- 1). Open a container of mud and transfer a quantity onto a palette made from a scrap piece of drywall. Using a 4-inch drywall blade, spread the mud generously along a seam from one end to the other. The mud should extend about two inches on either side of the seam, and there should be no voids, or areas without mud, along the seam.
- 2). Unroll enough drywall tape from a roll to cover the seam from end to end. If the tape is fiberglass, cut it off with a utility knife. If you're using paper tape, tear it off, then dip the piece you are going to use in water to moisten it.
- 3). Lay the tape on the seam that you mudded and scrape it flat with the 4-inch blade, starting at one end and working towards the other. Excess mud will squeeze out from under the tape as you scrape. Remove this as you go and return it to the palette for future use. When you are done scraping, the tape should be flat against the wall without bubbles or separation. Add a little more mud under areas where the tape isn't adhering; then re-scrape it.
- 4). Spread a thin coat of mud on top of the tape and scrape it flat; then let the mud dry overnight.
- 5). Spread a second coat of mud over the tape and dried mud, this time scraping it with a 6-, 8- or 10-inch blade. The wider blade will create a flat covering over the seam that feathers into the surrounding drywall. Let this coat dry; then apply a third one in the same way. The third coat should hide the seam completely.
- 6). Mud and tape inside corners of drywall in a similar way. Spread mud on both sides of the corner, then fold the tape and lay it in the corner on top of the mud. Scrape each side of the corner with a drywall blade, then finish off with two top coats as you would a flat seam.
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