Drywall joint compound is used on drywall or sheetrock to patch gaps or holes. Often referred to as "mud", it can be easily mixed and applied to hide any imperfections and make wall joints appear seamless.
Tape and Taping Knives
The tools you will need are tape, taping knives, and a mud pan. Taping knives are narrow at the handle and flare out in a thin sheet of metal to a straight tip. There are various types of taping knives. Some are small, some are made for corners, and others are wide for larger areas.
Drywall tape is used for corners and other areas where sheets of drywall meet one another. The reason for the tape is that these areas are more susceptible to cracking. The tape helps prevent pressure or friction from cracking the joints.
A mud pan is necessary to hold small amounts of drywall compound. This is useful if you are working with a five-gallon bucket of mud. Rather than working out of the bucket itself, you can place the compound in the mud pan and easily apply using the taping knives. Do not put any used mud back into the five-gallon bucket, as this may contaminate the fresh mud.
Mixing the "Mud"
Most drywall compounds come in either one-gallon or five-gallon buckets. The size of the job will determine how much you need. Deeper joints and heavier finishing will require more compound. The easiest way to mix drywall compound is to use a mixing paddle. Using a drill, attach the paddle bit. Now slowly begin mixing the compound. The consistency you are looking for is creamy-like. You don't want any thick pieces in the mud. Do not use drywall compound that is dry.
After you have all the necessary tools and the compound is mixed, it's time to begin "mudding." The choice of taping knives will depend on the size of the wall cavity. If you are patching a small dent, a regular six-inch knife will do. Placing the knife in the mud pan, scrape out an amount of mud adequate to the patch area. Any excess mud can be scraped off the wall with the knife. For corners, you will need the drywall tape. Fill the corner with plenty of drywall mud.
Now tear off a strip of tape equal to the distance of the corner. Using a corner taping knife will make this easier, but a regular one will do. Slowly place the tape over the mud, making sure half of the tape is on one side of the corner and half is on the other. Use your taping knife to press the tape into the mud. Use caution not to tear or slice through the tape. When finished, the face of the drywall tape must be mudded too.
Cleaning up drywall joint compound just requires a little elbow grease and water. Rinse all tools and equipment. Dried mud may need extra rubbing to remove. Use caution when cleaning the knives to avoid cutting yourself.