Knock down any ridges or significantly imperfect areas through sanding, which should help you apply the next coat of mud smoothly. If your first coat of mud is pretty smooth after it dries, a quick sanding is all you'll need. Don't forget to wipe away any dust after each sanding process.
Whether you're an experienced or novice painter, sanding between coats of paint depends on the project and your personal preference. The good news is, you won't hurt anything if you decide to sand between each coat of paint.
Regardless of whether you prefer to paint or tile, your drywall must be installed correctly for a smooth finish. If there are any blemishes in the drywall, they will be visible in any paint job or prevent tiles from sticking correctly. One of the most important steps for finishing drywall correctly is sanding.
You don't have to sand between coats; just knock off lumps or proud mud lines with a 5- or 6-in. putty knife to avoid streaks in the next coat. Brush off the wall and you're ready for the next coat.
But they can all agree on one thing. If you see problems with the first layer, you need to apply another coat. Here's why your drywall might need multiple coats of mud.
Knock down any ridges or significantly imperfect areas through sanding, which should help you apply the next coat of mud smoothly. If your first coat of mud is pretty smooth after it dries, a quick sanding is all you'll need. Don't forget to wipe away any dust after each sanding process.
Mud straight out of the bucket is too thick for anything. Any pro will tell you that you must thin it down. You want it smooth and spreadable like pudding. You might have to remove a scoop of mud to make room for some water.
You only need to sand old walls before painting. Newly plastered walls should already have an even surface to paint onto, but old walls may have rough spots. The best way to identify the rough areas is to run your fingers over the surface and feel for changing texture.
Drywall mud can take as long as 24 hours to dry for thick applications. The 24-hour drying time recommendation can be applied to nearly all factors. Some manufacturers will bring down that number to 12 hours if a few shortcuts are applied to help speed up drying time without affecting the finished product.
Good air flow also helps speed things up. To dry mud quicker, pros use fans for better air circulation. Some also use heaters to warm up the room.
Joint compound is the same as drywall mud or just mud. It's comprised mainly of gypsum and limestone, but it also has other materials such as clay, mica, perlite, and starch. Joint compound has a spreadable consistency similar to mud, which is how it got its common name.
Sand Between Coats
Make sure to sand the polyurethane between coats. Sanding removes drips, bubbles and other uneven spots in each coat.
Key Insights for Successful Drywall Sanding
Keep Your Work Area Clean: Minimize dust with tools like dust-free sanders and regular cleaning. Know When to Stop: Continuously check your work for smoothness and uniformity to avoid over-sanding.
Apply a push-pull motion when using a hand sander or pole sander, applying even pressure inside the seams and along nail and screw patterns. Use semi-coarse sandpaper of 100 of 120 grit to sand down the rough areas or dried compound, then continue with 150 grit to smooth the areas further.
Another common blunder is using too little or too much joint compound. Uneven application can cause visible seams, cracks, or bulging joints, compromising the overall appearance of your walls.
Premixed joint compounds come in a variety of consistencies, depending on the brand, the factory where they were produced, and even regional formulas. The joint compound manufacturers allow users to add water to the compounds, but the formulas are designed be thinned with water only.
There are a few reasons that drywall mud may crack after it finishes drying. One of the main reasons is that the coat of drywall mud was applied too thickly. Another reason for cracking could be due to the type of drywall mud that was used. For example, premixed drywall mud dries through evaporation.
Apply Second (Filler) Coat of Mud
With the 10- or 12-inch drywall knife, apply a second coat of mud to the seam. This coat is sometimes called the filler coat. The tape should show through the filler coat. If it doesn't, your filler coat is too thick.
Fortunately, fast-drying setting-type compounds allow you to do just that. Setting-type joint compounds harden chemically in anywhere from 20 minutes or 30 minutes to 4 hours or 5 hours, depending on the type used. The compounds with the shortest setting times are ideal for one-day finishing.