Hello, I'm an expert in wood finishing with extensive knowledge in various types of finishes and their application processes.

Yes, you can put polyurethane over a lacquer finish, but there are a few considerations to keep in mind. Lacquer is a fast-drying finish that is known for its quick application and curing time, while polyurethane is a more durable and protective finish that provides a harder, more resilient surface.

Here are the steps and considerations for applying polyurethane over lacquer:


1. Preparation: Ensure that the lacquer finish is fully cured. Lacquer typically dries quickly, but it can take up to 24 hours for a final coat to harden completely.


2. Sand Lightly: Lightly sand the lacquer surface with a fine grit sandpaper (around 320 grit) to provide a key for the polyurethane to adhere to. This step is crucial because polyurethane does not bond well to a slick lacquer surface.


3. Clean: After sanding, clean the surface thoroughly to remove any dust or debris. You can use a tack cloth or a slightly damp cloth to wipe down the surface.


4. Apply Polyurethane: Apply the polyurethane according to the manufacturer's instructions. It's important to apply it evenly and allow it to dry as directed.


5. Consider the Sheen: If the lacquer has a high gloss, applying a high-gloss polyurethane will maintain that gloss. If you prefer a more matte or satin finish, choose a polyurethane with a corresponding sheen.


6. Multiple Coats: For added protection and durability, apply multiple coats of polyurethane, allowing each coat to dry fully before applying the next.

7.
Safety: Always work in a well-ventilated area and use appropriate safety gear, such as gloves and a mask, when applying finishes.

By following these steps, you can successfully apply polyurethane over a lacquer finish to enhance the durability and protection of the wood surface.

read more >>

First, whatever finish that is applied will never look as good as the one put on at the factory. Second, polyurethane is not the best choice for painting over lacquer finishes. Polyurethane will not bond or grip well with the lacquer and will peel off over time with general use. Instead, use an alkyd varnish.read more >>