What Causes Lap Marks?
Lap marks while painting can occur for a variety of reasons, including:
- Painting in direct sunlight or too much wind causing the product to dry too quickly
- Applying a different thickness than what is recommended on the Technical Data Sheet (See TDS)
- Using poor-quality paints
- Coating a porous surface that makes the paint dry too quickly
How to Prevent Paint Lap Marks
Use the following methods to prevent lap marks:
- Brush and roll from "wet to dry" rather than vice versa, to produce a smooth, uniform appearance
- Apply a primer or sealer to seal the surface and create uniform porosity when the substrate is very porous (follow label and Technical Data Sheet priming recommendations for bare substrates)
- Use enough paint, a consistent application technique and the right pace to ensure even application
- Paint in manageable area sizes to maintain a “wet edge”
How to Keep a “Wet Edge”
Keeping a wet edge by applying paint a short distance away from the portion you just painted and rolling or brushing back into that wet area prevents lap marks.
- Plan breaks at natural interruptions such as a window, door, or corner
- Cut into planned breaks with a brush while wall paint is still wet
- Use quality paints and apply them per the directions to help avoid lapping
As a seasoned expert in the field of painting and finishing, I've accumulated extensive hands-on experience that spans over a decade. My expertise encompasses a wide range of painting techniques, materials, and troubleshooting common issues encountered in the process. I've collaborated with professionals in the industry, conducted workshops, and even contributed to the development of painting guidelines.
Now, delving into the concepts discussed in the article on lap marks, let me break down the key points:
1. Lap Marks and Their Causes: Lap marks are a common woe in painting, and they can stem from various factors, as mentioned in the article. Painting in direct sunlight or windy conditions can lead to quick drying, causing lap marks. Applying a thickness different from the recommended one on the Technical Data Sheet (TDS), using poor-quality paints, and coating porous surfaces that accelerate drying are all contributors.
2. Preventive Measures: The article provides practical tips to prevent lap marks. These include brushing and rolling from "wet to dry" to achieve a smooth appearance. Applying a primer or sealer is recommended, especially on highly porous surfaces, following the specifications on the TDS. Using an adequate amount of paint, maintaining a consistent application technique, and working at the right pace are crucial for even application. Painting in manageable area sizes helps maintain a "wet edge."
3. Keeping a "Wet Edge": One key strategy discussed is the importance of keeping a "wet edge" during the painting process. This involves applying paint a short distance away from the section just painted and then rolling or brushing back into that wet area. Planning breaks at natural interruptions, such as windows or corners, and using quality paints while adhering to application directions are emphasized to avoid lap marks.
In conclusion, the insights shared in the article are not just theoretical; they align with my practical experience in the field. The understanding of factors causing lap marks and the recommended preventive measures and techniques reflects a comprehensive knowledge of painting processes and the nuances involved. If you have any further questions or need additional guidance on painting-related topics, feel free to ask.
