Wooden door painting process?

Instructions for the paint process of making wooden doors: Making wooden doors requires many steps, from the selection of wood, dehydration, application of veneer, to polishing and painting of wooden doors. The quality of the manufacturing process of these wooden doors is directly related to the quality of the finished brand wooden doors. Among them, wooden door painting is a post-production process of wooden door production, which directly affects the final use effect of solid wood doors and solid wood composite doors. A good painting process can not only make the veneer texture of the solid wood door clearly visible, but also protect the wood of the solid wood door from the penetration of moisture in the air, making the solid wood door and solid wood composite door have a longer service life. The common types of paints on the wooden door market are roughly divided into six types: phenolic paint, alkyd paint, polyurethane paint, nitrocellulose paint, polyester paint and PU paint. Among them, phenolic paint and alkyd paint are basically eliminated in decoration due to poor texture and adhesion of the paint film. Nitrocellulose paint, polyester paint and PU paint are widely used. Because the construction of nitrocellulose paint is relatively simple and suitable for manual operation, it is used by most hand-made decorative wood. However, the paint film is thin and the hand feel is not good, so the effect is not ideal in the production of wooden doors in Weifang. Polyester paint has a relatively thick film, but its diluent contains radon gas when it evaporates, and the film hardness is slightly weaker. The most ideal is PU paint. PU paint not only has the advantages of thick film, strong adhesion, and good transparency of polyester paint, but also has good sealing properties and plays a very important role in moisture-proofing solid wood doors. PU paint The hardness, durability, yellowing resistance and environmental protection are also unmatched by other paints. As far as painting is concerned, generally speaking, when using polyester paint and PU paint, there are six wooden door production and painting processes, including color search, three bases and two sides. As a wooden door manufacturer, you must use high-quality wooden door paint when painting the wooden door, and operate according to the prescribed manufacturing process to ensure the texture and durability of the wooden door. Characteristics of various wooden door painting processes: There are many different processes for wooden door painting. The principle of process design is to select the appropriate paint variety, determine the painting operation process, and configure the related equipment according to the customer's requirements and standards for wooden door products. From the surface effect requirements of wooden door products, we can divide them into fully enclosed effects. . .

There are many different processes for wooden door painting. The principle of process design is to select the appropriate coating variety, determine the coating operation process and configure the related equipment according to the customer's requirements and standards for wooden door products. In terms of the surface effect requirements of wooden door products, we can divide them into fully closed effects and semi-open effects (including fully open effects); at the same time, they can be divided into transparent effects and solid color effects. In the market, we can see that the surface coating effect of most wooden door products is a fully enclosed, transparent and colored effect, and the coating types used are mainly PU paint. In this article, we will use PU as the fully enclosed transparent colored effect of the coating to introduce the process and analyze the advantages and disadvantages of each process. The above basic process is suitable for the painting and coating operations of most wooden door companies. However, each factory has made some adjustments based on the above process based on the product positioning and materials used by their respective companies, and has derived many different processes. The following is an introduction to various derived process processes: One base and one side 1. Process flow: White blank polishing → scraping ash → polishing → spraying transparent primer → polishing → spraying colored transparent surface 2. Product positioning: low-end product. 3. Advantages: The process is the simplest and the painting cost is the lowest. When there are obvious defects in the white wood blank, use wood-colored water ash to fill them. The colored transparent surface can be sprayed with a darker color to make it easier. It can well cover the defects of the substrate. The color is uniform. 4. Disadvantages: The product is not transparent and the natural texture of the wood cannot be seen clearly. The entire coating effect is similar to that of solid color paint on medium density board. After applying a primer, the product has poor filling properties and poor sag resistance, and the paint film on the surface of the product is prone to undulations, which greatly affects the overall aesthetics of the product. Sanding with water ash is the most time-consuming and labor-intensive. High strength and heavy dust make it difficult to polish. Part 2: Two bottoms and one side (including water ash type) 1. Process flow: white blank polishing → scraping water ash → polishing → spraying with transparent primer → polishing → spraying with transparent primer. Paint → Polish → Spray the colored transparent surface. 2. Product positioning: mid- to low-end. 3. Advantages: The process is relatively simple, the coating cost is low, and it has better filling and sag resistance than the previous process.

4. Disadvantages: The permeability of the product is not very good, the sense of layering is not strong, and the natural texture and beauty of the wood cannot be well displayed. The sanding strength of water ash is high and the dust is large. 5. Suggestions: (1) Change the wood-colored water ash to "colored water ash"; (2) Change the colored transparent topcoat to use color-correcting essential oil to repair the color, lightly sand, and then spray the transparent topcoat. This will greatly improve the transparency and layering of the product, allowing the texture of the wood to be expressed more clearly, while the overall cost will not increase much. Part 3: Three bottoms and one side 1. Process flow: Polish the blank → spray transparent primer → polish → spray transparent primer → polish → spray transparent primer → polish → color repair → light sand → spray clear topcoat. 2. Product positioning: mid-to-high-end products. 3. Advantages: It has good permeability and can clearly show the natural texture of wood. The construction of water ash is omitted and the intensity of polishing is reduced. 4. Disadvantages: The cost is high and the process has not been simplified. If it is a material with deep wooden eyes, three primers cannot achieve good fullness. If the wood grain texture of the material is thin, the effect of the wood grain texture cannot be enhanced (it is only a true representation). 5. Suggestions: (1) If the material has deep wood holes, the second primer can be wet-on-wet; (2) The second primer can also be changed from spraying to scraping, which not only saves a lot of money cost, and the resulting coating effect is better. Four: Bottom coloring, surface color correction 1. Process flow: white blank polishing → spray sealing to solidify the bottom → polishing → rub PU Grace → spray transparent primer → polish → spray transparent primer → polish → spray transparent primer → Sand → color correction → light sanding → spray clear topcoat. 2. Product positioning: high-end products. 3. Advantages: It has very good permeability and layering (three-dimensional sense). Even if the texture of the wood itself is not clear enough, the texture can be expressed more clearly through the above process operations. 4. Disadvantages: high cost and long operation time. 5. Suggestions: (1) If the texture of the wood itself is very clear and beautiful, there is no need to use base coloring (such as Sapele's veneer, use a transparent primer directly, the wood eye itself will emit a flashing red effect, It is very beautiful; but if you do the base coloring process, this effect will not be visible); (2) After using the base coloring process, the surface color can be lighter, so that the layering and permeability are better. Through the above process introduction and analysis, we can see that each process has its applicability and its advantages and disadvantages. Therefore, when we choose a process, we must consider the actual needs and conditions to choose the appropriate process. Otherwise, it will be difficult to achieve our ideal effect, sometimes it will cost more, and we will not be able to achieve the effect and quality we want. . Today, as the wooden door manufacturing industry becomes more and more prosperous, it also means that competition in the industry has become increasingly fierce. The overall trend of profit margins in wooden door manufacturing and sales is getting lower and lower. How to control costs, improve quality, and improve production efficiency to the greatest extent is a topic that faces every practitioner. Does improving quality mean increasing costs? On the surface: yes. But it's not. Some people say that I want the effect of the "base coloring and surface color correction" process, but I also want the process to be simpler and cheaper. In fact, it can be done. Some factories are already maturely using new materials to replace the previously used water ash, so that they not only have good filling and construction properties, but also achieve the effect of base coloring. The use of new materials can optimize processes, reduce costs, and improve efficiency. When paint was first applied, people mostly used brushing. Later, they switched to spraying, which greatly improved production efficiency and quality. But people ignore that there are many methods of painting. Some factories choose the scraping method, which not only greatly saves costs, improves efficiency, but also produces better results. Therefore, painting as a science, like all other scientific fields, has endless exploratory potential. It is always progressing and developing. Answers to Engineer’s Questions Question: The surface of the door we just made is very smooth, but after leaving it for more than a month, we found that the surface gloss is not so bright and the surface is not so smooth. What is the reason? Answer: Mainly due to the paint film sinking. The sinking of the paint film will cause the surface to be uneven, and the uneven surface will cause light reflection and scattering, resulting in a decrease in gloss.

Countermeasures: The bottom layer must be sealed, the wooden holes must be filled in during the bottom painting operation, the drying time must be sufficient, and the sanding must be thorough, so that the occurrence of the above situation can be better controlled. Question: The average paint cost for painting a set of doors (5.3 square meters) is more than 200 yuan. For this reason, we have changed several paint suppliers. The unit price of paint has dropped a bit, but the overall cost remains high. How can we reduce the cost? ? Answer: Cost control of painting is a systematic project. Just choosing a cheaper paint unit price cannot solve the fundamental problem. We believe that we can start from the following three aspects: first, choose the most suitable process; second, control the rework rate; third, improve the quality of operators.