How to Wet Sand Sheet Rock

There are several steps taken after installing new sheet rock walls or just replacing and repairing small pieces of sheet rock on a damaged wall. The most common way of finishing sheet rock joints is to sand with sand paper which creates a large amount of dust. There is an easier way to sand sheet rock which will create less dust throughout the house. This is especially useful when living in the home while this work is being done. It is probably the cleanest way to finish sheet rock walls.

Things You'll Need

• Sheet rock tape
• Joint compound (otherwise known as mud)
• Mudding pan
• 6" taping knife
• 10" finishing knife
• 12" finishing knife
• Bucket
• Water

Instructions

Wet Sanding Sheet Rock

1. Keep a supply of joint compound in the mudding pan for easy access. Using the 6" taping knife, run the mud along the seam where the two pieces of sheet rock meet making sure the seam is filled. Place the sheet rock tape over the mud pressing lightly. Run another layer of mud over the entire width of the sheet rock tape smoothing out as you are moving along. Putting compound on too thick will cause it to crack. Let this completely dry.

2. Using the 10" finishing knife, put another layer of mud on top of the previous layer. This layer is going to extend over the edges of the original layer that was done with the 6" knife. When putting it on, spread it out creating a thin layer. Smooth as much as possible removing any lumps or air pockets with the knife. Let this completely dry.

3. Using the 12" finishing knife, put the final layer of mud on top of the previous layer. Make sure that the mud you are using is smooth. You can add a little bit of water to it to make it thinner at this point. As you are placing it over the previous layer, smooth it out to the sides (feathering) until it is barely visible. Let this dry completely.

4. Fill a clean bucket with warm water and a sponge. Squeeze the water out of the sponge and lightly begin to go over the joint. This is wet sanding. The water will smooth out any bumps and ridges left on the dry mud. Make sure to sponge the entire area working your way to the sides so that the mud seems to disappear. Run your hand over it to check for any unseen bumps. Let this dry completely.

5. If the joint looks and feels smooth when dry, the wall is now ready for primer. If it needs further smoothing out, you can repeat the wet sanding on just those areas.

Tips & Warnings

• Do not leave chunks of mud to dry on the wall.

• Smoothing out with the knife while mud is soft will cut down on necessary sanding.

• Always keep the joint compound container covered since it can dry out quickly.

• Dry compound will create rocks or bumps on the sheet rock.

• Stir up the compound to make it thinner.

• Rinse the sponge out often while wet sanding to remove the excess mud.

• Use this same method to cover any screws in drywall.

• Always wear a mask.

• Mud is very drying to the skin. It is advisable to wear gloves.

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