[Woodware] Six tips on wood lacquer painting
The correct coating construction method can make the coating perform professionally. As far as wood lacquer is concerned, if you want to get good results, you must pay attention to the construction method. Here are six tips for wood lacquer construction.
Wood lacquer construction tips 1:
Answer: Dust removal in advance. First of all, the surface of the wood should be polished flat, and the floating ash should be treated. When cleaning, a special dust-removing cloth can be used, and a large area (such as a floor plate) should be repeatedly vacuumed with a vacuum cleaner.
Wood lacquer construction tips 2:
A: It varies from material to material. Understand the wood of the wood, if it is hard wood (such as teak, beech, Bengals), you should use putty, foaming water, etc. as a primer to avoid discoloration and affect adhesion. For hard wood, if you want to get the best effect, you can directly paint it. If you need to fill the gap, it is recommended to mix it with paint and fine wood powder. For ordinary wood, if you need to use transparent putty as the substrate, you should use The scraper should evenly scrape the entire base layer. It should be thin and not thick. After drying, it should be polished evenly and the excess transparent putty attached to the surface of the wood should be thoroughly polished to avoid paint disease.
Wood paint construction tips three:
Answer: Ready. The environment and brushing tools must be clean when painting. Operators should wear clean work clothes and work caps.
Wood lacquer construction tips four:
Answer: Coating grasp. The paint should be thin and not thick, and it can be carried out in multiple layers; when doing multi-layer painting, each painting should be applied after the lower layer is dry, and it should be polished every time.
Wood lacquer construction tips five:
Answer: suitable temperature construction. When the temperature drops below 5°C, the drying time will be prolonged. At the same time, if the temperature is too low, white fog or extinction will occur. Therefore, construction should be avoided in this situation; avoid operating under direct sunlight or high temperature. If the temperature is too high, the paint will dry faster. , pinholes or bubbles will also occur, so high temperature construction should also be avoided as much as possible.
Wood lacquer construction tips six:
Answer: Humidity control. When the ambient humidity is greater than 85%, it is not suitable for construction, otherwise it is easy to cause problems such as whitening of the paint film.
Water-based paint application precautions
Furniture water-based paint is generally a single-component water-based paint, and there are strict requirements for environmental humidity, ambient temperature, dilution ratio, and construction methods.
The temperature cannot be lower than 0°C (the freezing point of water), otherwise it is easy to freeze and cause the paint film to fail to dry;
The temperature should not be too high. Too high temperature and too fast drying will lead to poor leveling, pinholes, and orange peel defects.
Since the drying process of one-component water-based paint is mainly the process of water vapor evaporation, the environmental humidity is the core factor affecting the evaporation rate (similar to solvent-based paint, the volatilization of the main diluent of solvent-based paint is affected by the concentration of the diluent. , This concentration is very low, so the surface drying of solvent-based paint is relatively fast) If the ambient humidity is too low (that is, the concentration of water vapor is low), the drying will be relatively fast, which may easily lead to poor leveling, pinholes, orange peel When the environmental humidity is too high, the water in the water-based paint film will evaporate very slowly, resulting in a long surface drying time, which is prone to sagging and other defects.
Dilution ratio: 0-25%
What will be diluted?
Mainly for three reasons:
l Control the moisture content in the paint to control the leveling and surface drying time;
l Control the viscosity of the paint to meet the best operating conditions of the painting equipment. Generally speaking, air spraying requires more water for dilution, while airless spraying or air-mixing spraying can add less or no water for dilution;
l Control the construction thickness, which generally occurs when the construction dry film thickness is relatively thin. Due to the lower limit of the spray flow rate of the spray tool, when very thin coatings need to be produced, it is difficult to meet the requirements without thinning the paint. At this time, the concentration of the paint is reduced by adding water to dilute it (in disguised form, the flow rate during construction is increased);
Construction tools: air spraying, airless spraying, air-mixing spraying, electrostatic spraying
Aside from the factor of equipment investment cost, when we choose construction tools, we should always consider the choice of equipment according to different processes, product characteristics, production efficiency and other factors.
Air spraying: mainly for the occasions where the paint film construction is relatively thin and the construction amount is small. For water-based paint construction, due to the relatively high viscosity of the paint, usually more than 30 seconds, this viscosity is difficult to atomize for air spraying. Therefore, the biggest disadvantage of using air spray to construct water-based paint is that the paint utilization rate is low and the construction efficiency is low.
Airless spraying: mainly for occasions where the surface quality requirements are not high and the paint film is relatively thick. Airless spraying can apply very high viscosity paints, so there is no need to deliberately consider the effect of paint viscosity on spraying. However, the biggest drawback of airless spraying is that the flow rate and atomization effect cannot be independently controlled, the controllability is relatively poor, and the atomization effect is not particularly ideal.
Air-mixed spraying: mainly for occasions with high surface quality requirements and relatively thick paint film (wet film thickness above 40 microns). Due to the technical characteristics of air-mixing spraying itself, it has the requirements of taking into account the quality, efficiency, cost and other aspects, and is the preferred tool for water-based paint construction. ,
Electrostatic spraying: For some applications that meet the electrostatic spraying conditions (workpiece conductivity, grounding effect, paint resistance, etc.). Electrostatic spraying is divided into air electrostatic, airless electrostatic, air-mixed electrostatic, electrostatic rotary cup, electrostatic rotary disc and other methods. Due to the relatively high viscosity of water-based paints, in practical applications, air-mixing electrostatic is the best choice. However, the application of water-based electrostatic is a relatively complex system engineering, and the investment is relatively high.
【Construction】Six ways to reduce paint construction loss
New Wall Walls:
Answer: The dust and foreign objects, cracks and peelings on the new wall will affect the painting effect and cause unnecessary wear and tear. Therefore, all dust and foreign objects on the wall should be brushed off first, and all cracks and peeling should be filled. Seam and level, and at the same time ensure that the wall is free of salt, grease and dragon's spine. When starting construction, the adjacent walls should be shielded to avoid spraying paint.
Answer: Because the old wall has been treated with foundation, all you need to do is to ensure that the base of the wall is firm. You can first rinse the wall with a soda solution, scrub it clean, and then use a sub to level the wall.
Brush or Roller:
Answer: To save paint, the construction should be done by brush or roller. In order to ensure the flatness and smoothness of the cover, it is suitable to spray with a spray gun, and the walls that do not need to be sprayed need to be covered in advance.
A: The different selection of nozzles will also affect the degree of paint wear. When using a nozzle with a smaller spray width, the loss will be lower, and the spraying effect of different brands of spraying tools is different, and the loss of paint is also different.
A: The best temperature for paint construction is 5-40 degrees, and the humidity is below 90%. Spring, summer and autumn are all suitable for wall construction. If spraying is used, the wind speed during spraying should be less than 6 meters per second, and the supply pressure of the air compressor should be above 60 Newtons.
A: Make a good construction plan and arrange the construction time. If the time is not enough, and blindly seek speed, the construction personnel may use the method of wasting the paint because of rushing the schedule, and it is not conducive to the guarantee of the decoration quality. If the owner buys the paint by himself, the amount of paint needed should be calculated according to the floor area of the home.
[Architecture] Six Steps of Exterior Wall Paint Painting Process
1. Substrate processing:
A: This is a very important process, because the new paint layer will make any old spots, stains and defects that have not been carefully treated stand out, which is also the direct cause of the peeling and chalking of the paint film in the future. Wall refurbishment is a big inconvenience. The right remedy is the most basic coating requirement, and different treatment methods are adopted for different base layers: if the substrate has holes or structural cracks, it must be repaired with a putty that is durable and easy to be embedded. The new wall should be maintained for more than 1 month. It is clear that the floating ash stains are very alkaline, and it is polished with coarse sandpaper into a rough construction surface, which is conducive to the adhesion of the paint film. If the old wall is flat and intact, it can be repainted directly after cleaning the surface. If the old coating has been chalked, cracked or peeled off, rinse with high pressure water or remove the old film and repaint the primer twice and topcoat again.
2. Batch scraping putty:
A: After the base material meets the requirements, if you need to better reflect the topcoat effect and make the paint surface soft, delicate and plump, you can scrape a layer of putty in order to fill in the tiny gaps on the base material. After batch scraping, the wall surface should be naturally dried for more than 12 hours, then polished, and cleaned up before proceeding to the next process. The renovation project of old tiles and mosaics can directly scrape two external wall putties without removing old tiles and mosaics. To increase adhesion, a sealing primer can be applied between the substrate and the putty layer. The putty layer in the relief system can be selected and constructed according to the conditions of the base surface.
3. Construction of sealing and alkali-resistant primer:
Answer: The sealing primer can seal the alkaline substances in the base material and reduce the occurrence of the defects of the paint film. The wall without scraping the exterior wall putty must choose the sealing primer or the alkali-resistant primer according to its material condition. The oil-based exterior wall sealing primer should be diluted with the specified thinner during application. The wall after scraping the exterior wall putty can be directly topcoated, and the coating with low requirements does not need to be painted with primer.
Fourth, the construction of the relief paint middle coating (selected according to needs):
Answer: The vertical distance between the nozzle and the wall should be within the range of 40-80 cm, and different diameter nozzles should be selected according to different patterns. If you spray a spherical pattern, you can spray it directly, and then apply it on top after drying and curing. The size and density are required to be consistent, and it is not allowed to form a deviation or flow. , turpentine, etc. can be rolled, and then coated on top after it is completely cured. The construction method of the two-color relief paint is the first coat of colored topcoat, the second coat of main paint, and the third coat of top varnish.
5. Topcoat construction:
Answer: When applying the exterior wall paint, the force should be uniform and the action should be fast, so as to avoid repeated reciprocating brushing to affect the effect of the paint surface. When the exterior wall paint is applied by spraying, certain protective measures should be taken to avoid inhaling the spray and avoiding skin contact. The exterior wall painting sequence should be up and down, from the roof, gutters, column tops, beams and rafters to walls, doors, windows and bottom plates. Each of these parts must also be painted from top to bottom. When painting each part, do not stop in the middle. If you have to stop, you should also choose the original connection part of the house structure, such as the connection between the wall and the window frame. This avoids unsightly seams.
6. Matters needing attention:
Answer: 1. For construction in wet areas with more rain or high humidity, the surface drying time of each process should be extended accordingly. 2. It is forbidden to construct in climatic conditions such as high temperature and direct sunlight, rainy days, high humidity, temperature below 8°C, and strong wind. 3. The paint must be thoroughly stirred before use, and the construction gap should be tightly covered to prevent the paint from crusting. 4. Except wall putty cannot be sprayed, other sealing primers, alkali-resistant primers, exterior wall paints and varnishes can be sprayed. However, the paint consumption for spraying will increase accordingly. 5. It is not suitable for construction in rainy days, heavy fog, strong winds and other bad weather and when the temperature is below 10 °C and the relative humidity is above 85%.