Mirka® LEROS Wall & Ceiling and Drywall Sander

Drywall sanding requires specialized tools to ensure speed, surface quality, and safety. For professional results in the construction and renovation industry, the following Mirka tools are recommended:

• Mirka® DEROS Electric Sander: Compact, ergonomic, and designed for low vibration. Offers excellent efficiency for sanding drywall surfaces. Compatible with dust-free systems.
• Mirka® LEROS: Lightweight, random orbital sander with a flexible 180° sanding head. Ideal for large drywall areas, reducing operator fatigue and improving precision.
• Mirka® LEROS-S: Short random orbital sander suited for confined spaces such as bathrooms and corners. Offers the same ergonomic benefits and dust-free compatibility as the full-size LEROS.
• Dust Extractors: High-performance vacuums engineered to maintain a dust-free environment. They reduce airborne dust and improve abrasive performance by preventing clogging.

Selecting high-performance abrasives is essential for achieving a smooth finish while maintaining efficiency and safety:

• Abranet®: A net-structured abrasive developed for dust-free sanding. Its mesh design allows for excellent dust extraction, helping reduce airborne particles and improve visibility while working. Abranet supports a cleaner environment and longer abrasive life, making it ideal for drywall sanding tasks.
• Iridium™ Styro: A durable abrasive designed for tough surface sanding tasks like removing popcorn ceiling texture and smoothing heavy wall textures. Its structure helps eliminate sanding debris when used with polystyrene insulation panels and textured surfaces. Best used with Mirka® LEROS, LEROS-S, and dust extractors for clean, efficient results.

To ensure operator safety and maintain an efficient workflow:

• Use Mirka’s dust-free sanding systems, combining net abrasives with advanced dust extractors to minimize dust exposure.
• Set up proper ventilation and clear the workspace of obstacles.
• Provide personal protective equipment (PPE), including safety glasses, hearing protection, and a dust mask or respirator, even when a dust extraction system is in use. Select equipment based on the specific safety needs of the work environment.

For small areas or touch-ups, hand sanding offers precision and control. Always use a sanding block or hand sanding tool to maintain even pressure. Sand in light, circular motions or follow the seam lines to prevent creating grooves.

Keep the tool flat against the surface to avoid gouging. Abranet® abrasives are recommended for hand sanding because their open mesh structure allows effective dust removal.

Proper hand sanding techniques reduce the chance of surface defects and support a clean, professional finish.

Power sanding is ideal for larger drywall areas. Use lightweight, ergonomic sanders that offer consistent movement and dust extraction. The Mirka® DEROS electric sander is designed for efficiency and operator comfort.

For walls and ceilings, the lightweight and ergonomic Mirka® LEROS or LEROS-S provides flexibility and reduces fatigue. Keep the sander moving evenly across the surface. Avoid pressing down too hard, which can damage the drywall. Consistent, even sanding speeds up the process and delivers a smooth surface ready for finishing.

Effective dust management protects workers and improves sanding performance. Mirka’s dust-free sanding systems combine net abrasives like Abranet® with high-performance dust extractors.

This system captures dust at the source, keeping the workspace cleaner and reducing airborne particles. Minimizing dust improves visibility, reduces cleanup time, and protects your health.

In addition, maintaining a clean environment helps abrasives last longer and ensures consistent sanding results throughout the project.

Begin by inspecting the drywall panels for any loose fasteners, rough edges, or damaged corners. Tighten any screws that are not flush with the surface and recess any that stick out. Damaged sections should be repaired or replaced before continuing.

It is important to ensure all panels are securely attached and that gaps between sheets do not exceed 1/8 inch. This prevents future movement or cracking in the finished surface.

Next, clean the entire surface to remove dust, debris, or grease. Any contaminants can reduce the adhesion of the joint compound. Wiping the surface with a damp cloth or vacuuming with a brush attachment is often the most effective method.

Pay close attention to corners and seams where debris often collects. Working in a well-lit area is essential because proper lighting will help reveal imperfections that could be missed, especially at joints and corners.

Finally, lightly sand any rough spots or high edges using a sanding block or appropriate tool. This will create a smooth, even surface that allows the joint compound to bond effectively and reduces the amount of sanding required later in the process.

Start by applying a thin layer of joint compound over each seam using a drywall knife. This first layer, known as the bedding coat, helps secure the tape to the surface. Immediately after applying the bedding coat, press the joint tape firmly into the wet compound. For inside corners, crease the tape along its center before positioning it to ensure a snug, precise fit.

Using the drywall knife, smooth the tape into the compound. Apply firm, even pressure to embed the tape fully while removing any excess compound. It is important to avoid trapping air beneath the tape, as air bubbles can lead to weak spots or future cracking.

If a bubble forms, gently lift that section of tape and reapply it. The tape should lie flat against the drywall with no wrinkles or folds, which can cause visible defects later.

When working in inside corners or confined areas, use a narrower drywall knife. This allows better control and reduces the risk of damaging the tape or applying too much compound.

Taking the time to apply the tape accurately and smoothly will reduce the need for corrections in later steps and improve the final appearance.

Once the tape is in place, apply the first full coat of joint compound over the taped seams. Use a wider drywall knife, typically between 8 and 10 inches, to spread the compound smoothly and evenly.

Extend the compound slightly beyond the tape’s edges to create a gentle, gradual transition between the seam and the surrounding drywall. This minimizes visible lines once the surface is painted or finished.

Apply even pressure as you work to feather the edges of the compound. Pressing harder at the outer edges and lighter in the center helps prevent ridges and reduces the amount of sanding required after drying.

Keep the layer thin to avoid cracking or shrinking as the compound dries. Smooth, continuous strokes are essential for maintaining consistent thickness and reducing knife marks.

Allow the compound to dry completely before moving to the next step. Drying times vary based on the type of compound used and the environmental conditions at the job site, such as humidity and temperature.

Rushing this step can lead to poor adhesion or surface defects that will affect the durability and appearance of the final finish. Using proper technique and allowing adequate drying time ensures a smooth, professional result that will hold up over time.