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Putty powder common problems and solutions

2022-12-07

★Bubbles★
Phenomenon: Bubbles are generated during the construction process and after a period of time, the surface of the putty is blistered.
  cause:
1. The base is too rough and the plastering speed is too fast.
2. The putty layer is too thick for one construction, greater than 2.0mm.
3. The moisture content of the grassroots is too high, and the density is too large or too small. Due to the rich voids and the high moisture content of the putty, it is airtight, and the air is enclosed in the void cavity, which is not easy to eliminate.
4. After a period of construction, the bursting and foaming on the surface is mainly caused by uneven stirring. The slurry contains powdery particles that are too late to dissolve. After construction, a large amount of water is absorbed, swelling and bursting.
  Solution:
1. If there is a large area of bubbling putty surface, use a spatula to directly break the small bubble opening, and then use a suitable putty to scrape the bubbling surface layer again.
2. After the putty is stirred evenly, let it stand for about 10 minutes, then stir it again with an electric mixer and put it on the wall.
3. If foaming occurs in the second or last surface layer of construction, use a scraper to remove the bubbles before removing the watermark to ensure that no bubbles appear on the putty surface.
4. For particularly rough walls, the general primer should be as thick as possible.
5. In an environment where the wall is too dry or the wind is strong and the light is strong, first moisten the wall with clean water as much as possible, and then scrape the putty layer after the wall has no clear water.
★Powder removal★
Phenomenon: After the construction is completed and completely dried, the powder will fall off when touched by hands.
  cause:
1. The polishing time of the interior wall putty powder is not well grasped, and the surface will be de-powdered after the surface is dry.
2. For exterior wall putty powder, the coating is relatively thin when facing. In the high temperature in summer, the water evaporates quickly, and the surface layer does not have enough water to cure, so it is easy to fall off the powder.
3. The product has exceeded the shelf life, and the bonding strength has dropped significantly.
4. The product is not stored properly, and the adhesive force will drop significantly after absorbing moisture.
5. The high water absorption rate of the base layer causes the putty to dry quickly and there is not enough water for curing.
  Solution:
1. When polishing the putty surface of the interior wall, it is necessary to master the appropriate polishing time. The best time for polishing is to polish immediately after the watermark on the putty surface disappears. Practice has proved that the surface of 1~2m2 should be flattened or polished.
2. After the surface of the exterior wall putty is dry, it should be moderately polished and fully watered for maintenance. The general maintenance is divided into two or more times. If necessary, please use a transparent sealing primer mixed with water (1:5 ) as the second water spray, the effect will be better.
3. The product must be used within the shelf life. If it exceeds the shelf life, a trial scraping must be carried out. After passing the inspection, construction can be started.
4. The product must pay attention to waterproof treatment, and it should be stored in a cool and dry place, and the packaging should be guaranteed to be intact.
5. In summer or under high temperature and strong wind conditions, it is best to wet the wall with clean water before applying the putty. After there is no clear water on the wall surface, the putty can be applied.
★Delamination★
Phenomenon: The two layers of putty or between the putty and the substrate peel off each other.
  cause:
1. The substrate contains a large amount of release agent (such as waste engine oil, wax emulsion).
2. The substrate is severely pulverized and the water absorption is too large.
3. The putty at the bottom layer is severely pulverized, and if the putty at the bottom layer is too hard, it will also dry out too quickly and cause it to fall off.
4. The construction interval between two layers of putty is too long, generally more than 15 days, and the finish layer may sometimes cause delamination.
5. After construction or during construction, the putty layer is infiltrated by rainwater or other seepage water, which will cause the effective components of the putty to lose and fall off.
6. The combination of two layers of putty is unreasonable.
  Approach:
1. Remove the exfoliated layer and re-select the special putty for plastering.
2. For the severely pulverized construction surface, it is best to seal it with 10% sealing primer diluent, and then carry out the corresponding putty layer or other construction after drying.
3. For putty, especially for interior wall putty, the interval between two putty constructions should be shortened as much as possible.
4. Pay attention to the protection during the construction process. During the putty construction process or within 8 hours after construction, the putty is best not to be soaked by water.
★Crack★
Phenomenon: After a period of putty construction, the surface cracks.
  cause:
1. Construction is carried out before the base is completely dry, and the construction requires the moisture content of the base to be ≤10%.
2. If the putty on the bottom layer is not completely dry, it is passed over the surface, the surface layer is dried first, and the inner layer is still in the process of drying, resulting in different degrees of drying shrinkage between layers and easy cracking.
3. During the treatment of the base layer, if the seam filling and leveling materials are not completely dry, the inner wall putty with strong hardness is applied on it, which is easy to cause cracking.
4. If the construction is too thick, the interior will dry slowly and the surface will dry quickly, which will easily cause cracking.
  Solution:
1. The putty that has been cracked needs to be eradicated. If the crack is not too large, flexible putty can also be used for the first construction, and then the construction should be carried out according to the standardized construction method.
2. Each layer of construction should not be too thick, and the time interval between two layers of construction must be more than 4 hours. After the front layer of putty is completely dry, the subsequent layer of putty should be scraped.
★turn yellow★
Phenomenon: It means that after the putty construction is completed, part or all of it will appear yellow soon.
  cause:
It mainly occurs on old indoor walls. The old wall putty uses a large amount of PVA glue. The glue ages and decomposes, producing unsaturated acid. The unsaturated acid reacts with calcium ions in the putty to form a corresponding yellow calcium salt.
  Solution:
1. Use environmental glue to roll and coat twice, and then apply putty on the inner wall after it is completely dry.
2. Roll two coats of sealing primer, and after it dries completely, scrape the putty again.
3. All use paste putty for construction, or use plate putty for construction.

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Prescribe the right medicine to solve the five major problems of putty scraping

Putty is the same as paint construction, it is easy to cause various surface problems such as cracking, powder falling, air bubbles, etc. due to substandard material quality or improper construction. Everything is forewarned, so let us first understand some common quality problems of putty scraping, and take corresponding measures during construction to prevent these problems from appearing.

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