How to use wall putty:Master these six steps to smooth as new walls (so easy!)

Wall putty is an indispensable material in wall decoration, which can fill the cracks and level the grassroots, laying the foundation for the subsequent application of latex paint or wallpaper.However, many novices cause wall blistering, cracking or unevenness due to improper operation.In this article, So how to use wall putty?we will combine practical details and pit avoidance guide to teach you to master the correct use of wall putty from scratch.

I. Pre-construction preparation: list of tools and materials

core material

Putty powder: It is recommended to choose environmentally friendly finished putty (no need to add glue), and choose water-resistant type for humid areas.

Mesh cloth/kraft paper: used for wall crack reinforcement (crack width>1mm need to be used).

Water: for mixing putty, clean and free of impurities.

List of tools

Electric mixer (or manual stirring bar)

Stainless steel batch knife (recommended 20cm wide main scraper + 10cm narrow scraper for edges)

Sandpaper (240 mesh or above) or electric sander

Tray, measuring cup, lighting (side light to check flatness)

Protective equipment: mask, goggles, gloves

Ⅱ. six steps: standardized construction process

Step 1: Substrate treatment - the key to determining the life of putty

Shovel the peeling and hollow drum part of the old wall surface, and clean the floating dust with wire brush.

Gypsum fill the obvious depression (deep pits need to be filled in several times, single thickness ≤ 5mm).

Apply interface agent (wall solid): enhance the adhesion of putty to avoid delamination.

Step 2: Putty mixing - scientific proportioning to avoid overturning

Add water according to the proportion of product description (usually water-powder ratio 1:2.5), add water first and then pour the powder.

Stir until no particles of yogurt-like, let stand for 5 minutes second stirring to release the gelatinous.

Tip: Use it up within 30 minutes in summer to avoid solidification and waste.

Step 3: First coat - leveling mainly

Use a wide scraper to scrape the full thickness horizontally at an angle of 60°, and control the thickness at 1-2mm.

Use narrow scraper to close the edges at the corners to avoid piling up.

Avoid potholes: do not repeatedly scrape back and forth, otherwise it is easy to bring up the grass-roots level.

Step 4: Hanging mesh to prevent cracking - detail reinforcement

Paste the mesh fabric at the slots and the joints of the old and new walls, and cover and smooth with putty.

Ceiling screw caps need to be dotted with anti-rust paint before applying putty.

Step 5: Second Fine Scrape - Flatness Improvement

After the first coat is completely dry (24-48 hours, depending on humidity), thinly scrape vertically.

Focus on repairing air bubbles, sand holes, scraper strength needs to be uniform.

Step 6: Sanding and polishing - determining the final texture

Use 240 grit sandpaper with an LED light side by side and sand until there are no signs of stubble.

After sanding, use a brush to clean up the floating dust, acceptance criteria: no grain feeling by hand, no wave shadow under the light.

Ⅲ.HPMC for wall putty

HPMC is the core additive of wall putty, high-quality HPMC can improve the putty's water retention, anti-sagging flow, anti-cracking, but also play a thickening effect, choose Melacoll hpmc to ensure the quality of the product is reliable, the purity of up to 97% in the use of the amount of control in the 0.3% -0.5% can be the perfect wall putty in the best state of construction.

IV. 5 Common Problems and Solutions

1. What should I do if the putty layer blisters?

Reason: Uneven water absorption of the base or too thick scraping.

Solution: Scrape thinly for the first time, and puncture the bubble immediately to make up the scraping.

2.What to do when the bottom is exposed after sanding？

Cause: Over-sanding or too thin a putty layer.

Solution: partial re-scraping → second sanding.

3.What if the corners are not vertical?

Tools: Use a special trimmer for shaded corners, with a laser level for calibration.

4.What to do in winter construction cracking?

Control room temperature > 5 ℃, prohibit the addition of unknown glue to accelerate drying.

5.Grinding Dust Treatment

Recommended to use vacuum cleaner + slightly wet sponge double cleaning method, to avoid the dust affects the adhesion of the paint surface.

Can I use wall putty at home?

Strictly following the six steps listed above is perfectly fine to use at home, with the caveat that you'll need to have a full complement of tools and materials on hand.

V. Acceptance criteria and advanced techniques

International standard: 2 meters ruler check, wall flatness error ≤ 3mm.

Masking test: Tear it off after 48 hours of sticking on the wall, no powder removal is qualified.

Masterful Secrets:

Add 5% white latex to improve flexibility (non-finished putty only)

Use 200W light bulb to shine diagonally when polishing, it is easier to find the small defects.

Conclusion

Mastering the correct wall putty construction techniques will not only save more than 30% of the decoration cost, but also lay a solid foundation for the subsequent decorative effect.Remember: patience is more important than technique, and you can't cut corners on the drying time of each layer.Hands-on practice is recommended to practice on a small area of the wall first, and then carry out whole-house construction after skillful.For a wall putty formula click on View.