In the market, we can see that most wooden door products have a fully enclosed transparent colored coating effect, mainly using PU paint. This article will introduce the process of achieving a fully enclosed transparent colored effect with PU paint and analyze the advantages and disadvantages of various processes.
This basic process is suitable for most wooden door manufacturers' painting operations. However, different factories have made adjustments based on their product positioning and the materials they use, resulting in many different process flows. Below, we will focus on introducing these various derived process flows.
One: One Primer and One Top Coat
1. Process Flow: Sanding the raw wood → Applying putty → Sanding → Spraying transparent primer → Sanding → Spraying colored transparent top coat.
2. Product Positioning: Low-end product.
3. Advantages: Simplest process, lowest coating cost. When the raw wood has obvious defects, wood-colored putty is used to fill them, and a darker color is sprayed on the colored transparent top coat, which can effectively conceal the defects of the substrate. Uniform color.
4. Disadvantages: The product lacks transparency, obscuring the natural beauty of the wood grain. The overall coating effect resembles a solid color paint applied to medium-density fiberboard. Because only one primer coat is applied, the product's filling ability and resistance to sag are poor, easily resulting in wavy, uneven paint film on the surface, significantly impacting the overall aesthetics. Sanding the water-based filler is the most time-consuming process, labor-intensive, and dusty, making it difficult to hire sanders.
Part Two: Two Primers and One Top Coat (including water-based filler)
1. Process Flow: Sanding the raw wood → Applying water-based filler → Sanding → Spraying clear primer → Sanding → Spraying clear primer → Sanding → Spraying colored clear topcoat.
2. Product Positioning: Mid-to-low range.
3. Advantages: Relatively simple process, low coating cost, better filling ability and resistance to sag than the previous process.
4. Disadvantages: The product's transparency is not very good, lacking depth and failing to showcase the natural grain and beauty of the wood. Sanding the water-based filler is labor-intensive and dusty.
5. Suggestions: (1) Change the wood-colored water-based paint to "colored water-based paint"; (2) Change the spraying of colored transparent topcoat to using color-correcting essential oil for color correction, light sanding, and then spraying transparent topcoat. This will greatly improve the transparency and layering of the product, making the wood grain more clearly visible, while the overall cost will not increase much.
Part Three: Three base coats and one top coat
1. Process flow: Sanding the blank → spraying transparent base coat → sanding → spraying transparent base coat → sanding → spraying transparent base coat → sanding → color correction → light sanding → spraying clear topcoat.
2. Product positioning: mid-to-high-end products.
3. Advantages: good transparency, which can clearly show the natural wood grain. It saves the construction of water-based paint and reduces the intensity of sanding.
4. Disadvantages: high cost, the process is not simplified, and if the wood grain is deep, three coats of base coat cannot achieve good fullness. If the wood grain is fine, it cannot enhance the effect of the wood grain (it is just a realistic representation).
5. Suggestions: (1) If the wood grain of the material is deep, the second primer can be applied by wet-on-wet operation; (2) The second primer can also be changed from spraying to scraping, which not only saves a lot of costs, but also achieves a better coating effect.
Part Four: Base Coloring and Top Color Repair
1. Process Flow: Sanding of raw wood → Spraying and sealing the base → Sanding → Applying PU glaze → Spraying transparent primer → Sanding → Spraying transparent primer → Sanding → Spraying transparent primer → Sanding → Color Repair → Light Sanding → Spraying clear topcoat.
2. Product Positioning: High-end product.
3. Advantages: It has very good transparency and sense of layering (three-dimensionality). Even if the wood grain itself is not clear, the above process can make the grain more clearly expressed.
4. Disadvantages: High cost and long operation time.
5. Suggestions: (1) If the wood grain itself is clear and beautiful, there is no need to use base coloring (such as Sapele veneer, which can be directly coated with transparent base paint, and the wood grain itself will emit a reddish effect, which is very beautiful; but if the base coloring process is used, this effect will not be visible); (2) After the base coloring process is used, the surface color can be lighter, so that the sense of layering and transparency 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 choosing a process, we must consider the actual needs and conditions to choose the appropriate process flow, otherwise it is difficult to achieve the desired effect, and sometimes we spend more costs but still cannot achieve the desired effect and quality.
In today's increasingly prosperous wooden door manufacturing industry, it also means that the competition in the industry is becoming more and more intense, and the overall trend of profit margin in wooden door manufacturing and sales is getting lower and lower. How to control costs to the greatest extent and improve quality Improving quality and increasing production efficiency are challenges facing every employee. Does improving quality necessarily mean increasing costs? Superficially, yes. But in reality, no.
Some people say they want the effect of a "base coloring, top color correction" process, but also want a simpler process and lower costs. In fact, it's achievable. Some factories are already successfully using new materials to replace the previously used water-based paint, giving it excellent filling and workability while still achieving the base coloring effect. The use of new materials can optimize processes, reduce costs, and improve efficiency.
When paint was first applied, brushing was the most common method; later, spraying was adopted, greatly improving production efficiency. Productivity and quality are both important. However, people often overlook the fact that there are various methods of coating. Some factories use scraping coating, which not only greatly saves costs and improves efficiency but also produces better results.
Therefore, coating, as a science, like all other scientific fields, has endless potential for exploration. It is constantly progressing and developing.
Engineer's Question and Answer
: Question: The doors we just finished had very smooth surfaces, but after more than a month, we found that the surface gloss was not as bright and the surface was not as smooth. What is the reason?
Answer: Mainly due to paint film sagging. Paint film sagging causes uneven surfaces, and uneven surfaces cause light reflection and scattering, resulting in reduced gloss. Reduce costs.
Solution: Ensure proper sealing of the substrate. During the initial coating process, fill any wood pores completely, allow sufficient drying time, and thoroughly sand. This will effectively control the occurrence of the above-mentioned problems.
Question: The average paint cost for painting a set of doors (5.3 square meters) is over 200 yuan. We've changed several paint suppliers, and while the unit price of the paint has decreased somewhat, the overall cost remains high. How can we reduce costs?
Answer: Cost control in painting is a systematic project; simply choosing cheaper paint per unit price won't solve the fundamental problem.
We believe we can start from the following three aspects: First, choose the most suitable process; second, control the rework rate; and third, improve the skills of the operators.