Indoor decoration putty scraping process

Applying putty in indoor decoration is a key step in wall treatment, which directly affects the flatness of the wall and the final coating effect. The following is a detailed construction process and key points:

1、 Preparation before construction

1. Inspection and treatment of wall base layer

Check for hollowing/cracks: Use a hollowing hammer to tap the wall, mark the hollowing area (where the sound is crisp), use a cutting machine to cut off the hollowing part, and repair it to be flush with the base layer.

Dealing with cracks: Fill small cracks directly with putty; Larger cracks (width>0.5mm) need to be slotted (V-shaped) first, filled with joint gypsum or crack resistant mortar, and then repaired with alkali resistant fiberglass mesh.

Cleaning the wall: Remove the original loose coating, floating dust, and oil stains, thoroughly clean with a broom or hair dryer, and ensure that the base is solid and free of debris.

2. Preparation of tools and materials

Tools:

Scraping tools: putty scraper (20-30cm wide), putty pallet, sanding paper (240 mesh/360 mesh/600 mesh), sandpaper holder.

Auxiliary tools: roller (used for interface agent), ruler (2m long, check flatness), corner protector, and masking paper (protect edges).

Material:

Interface agent (wall fixing), putty powder (waterproof putty or ordinary putty for interior walls), joint gypsum, anti cracking mesh fabric (fiberglass mesh or Dacron cloth).

2、 Detailed explanation of construction process

1. Brush interface agent (wall fixing)

Function: Enhance the adhesion between the wall and putty to prevent hollowing.

Operation: Use a roller to evenly apply the interface agent, ensuring no missed brushing. The drying time is about 2-4 hours (according to the product instructions), wait for the surface to dry before proceeding to the next step.

2. Repair the internal and external corners and cable trays

Yin Yang corner treatment:

Use a putty scraper to scrape the joint gypsum or putty along the internal and external corners, and use an internal and external corner correction tool to ensure that the lines are vertical and straight.

Repair of trunking: After the water and electricity renovation, the trunking needs to be filled with joint gypsum, covered with anti cracking mesh (width>10cm on both sides of the trunking), and leveled with putty.

3. Apply putty for the first time

Putty adjustment: Mix the putty powder to water in a ratio of 1:0.5-0.6 to form a paste, let it stand for 10-15 minutes, and then stir again until there are no particles.

Key points for scraping:

Starting from the upper left corner of the wall, use a scraper to scrape horizontally with even force to avoid missing or accumulating.

Single batch scraping thickness ≤ 2mm, excessive thickness is prone to cracking. If the flatness of the wall is poor, it can be repaired multiple times.

Drying time: about 12-24 hours at room temperature, wait for complete drying before polishing.

4. Polish the first layer of putty

Tool selection: Use a sandpaper holder and 240 grit sandpaper for large areas, and use 360 grit sandpaper for details.

Operation method: Polish horizontally along the wall, focusing on the joints and protrusions until the wall feels smooth. Use a ruler to check the flatness (error ≤ 3mm/2m).

Cleaning dust: After polishing, use a broom or vacuum cleaner to clean the wall surface to avoid dust affecting the next layer of putty bonding.

5. Apply putty for the second time

Purpose: To further level the wall and fill in the small flaws after the first polishing.

Scraping direction: perpendicular to the first pass (e.g. horizontal for the first pass, vertical for the second pass), ensuring even coverage.

Thickness control: The single thickness is ≤ 1-1.5mm, and the total thickness usually does not exceed 5mm (exceeding it requires layered construction).

Drying time: Same as the first time, perform a second polishing after drying (using 360 mesh or 600 mesh sandpaper with lighter force to avoid abrasion).

6. Third coat of putty (optional)

Applicable scenarios: The wall flatness requirements are extremely high (such as artistic paint, wall cloth base) or there are still minor defects in the first two coats.

Operation points: Apply a thin layer of putty, focus on repairing nail holes and sandpaper marks, and after drying, lightly grind with 600 grit sandpaper to the ultimate smoothness.

3、 Construction precautions

1. Environmental requirements

Temperature: Construction temperature ≥ 5 ℃, humidity ≤ 85%, to avoid slow drying and mold growth of putty caused by low temperature or humidity.

Ventilation: Maintain good indoor ventilation, accelerate drying, but avoid strong winds blowing directly onto the walls (which can cause cracking).

2. Quality control

Flatness inspection: Use a 2m ruler to check multiple angles, and if the error is greater than 3mm, rework and repair are required.

Vertical yin-yang angle: Measure with an yin-yang angle ruler, with an error of ≤ 2mm.

Avoid common problems:

Cracking: If the base treatment is not clean, the putty is too thick or dries too quickly, it is easy to crack. It is necessary to carry out layered construction and reserve curing time.

Hollowing: If the interface agent is missed or the adhesive strength of the putty is insufficient, it is necessary to ensure that the base layer is solid and the interface agent is evenly applied.

3. Finished product protection

When applying putty, use masking paper to protect door frames, window frames, switch panels, etc. to avoid contamination.

Clean up the dust on the ground promptly after polishing to prevent it from contaminating the wall after stepping on it.

4、 Subsequent construction connection

Brushing latex paint: After the putty dries, roll or spray the primer and topcoat (primer enhances adhesion, topcoat color adjustment).

Wall cloth/wallpaper pasting: The putty surface should be extremely smooth, and then pasted after brushing the base film (moisture-proof).

Art paint: According to the process requirements, special treatment may be required on the surface of the putty (such as roughening, scraping texture).

Summary

Scraping putty should follow the principle of “proper base treatment, layered scraping, and multiple polishing”, and strictly control the quality of each process to ensure that the wall is flat and firm, laying a good foundation for subsequent decoration. It is recommended for novice construction practitioners to start practicing from a small area or hire professional oil workers to avoid rework due to improper operation.