Last Updated on August 18, 2022 by Ernest Godia
When staining a piece of finished wood or furniture, you must decide whether to remove the topcoat first or work with it.
Can you stain over polyurethane? Or do you have to go through the hassle of removing the old finish before applying a new coat of stain?
If these questions apply to you, read along to learn whether you can stain over polyurethane and the steps you need to follow to give your furniture the new elegant look it deserves.
Can You Stain Over Polyurethane?
Yes. You can stain over polyurethane but only using gel stains. Gel stain colors the wood by creating a film over the surface. However, since gel stain does not penetrate wood, you won’t get the same grain patterns you’d get with a standard oil-based or water-based stain.
If you choose this option, start by cleaning the wood surface and fine-sanding it before staining. Wipe off the dust, then apply your gel stain and let it dry. Seal the stain again with a clear top coat to protect it.
Does Stain Stick to Polyurethane?
Regular oil-based and water-based stains do not stick to a polyurethane finish. Polyurethane covers the wood pores and forms a glossy, hard layer, making it impossible for standard stains to penetrate the wood or stick to the surface.
However, topical stains like gel stains contain urethane, the primary ingredient in polyurethane, which bonds to the existing poly base and stains the wood as required.
Can You Stain Over Water-Based Polyurethane?
Absolutely! You can stain over water-based polyurethane using a gel stain instead of a standard wood stain. Gel stain works without penetrating wood pores. Sand the wood surface slightly for the best results and use a water-based gel stain for better compatibility.
Can You Apply Oil-Based Stain Over Polyurethane?
Standard oil-based stain won’t work over polyurethane since the finish coat won’t let it seep into the wood. The stain will only wipe off the surface and leave it unstained. To stain over polyurethane with an oil-based stain, you can mix the stain with poly before applying or use a product like Minwax Polyshades, which is already a blend of stain and polyurethane.
How Do You Stain Wood Over Polyurethane?
If you want a fresh coat of stain on your finished wood furniture, you don’t need to strip off the polyurethane finish. Instead, you can use a gel stain to refresh your wood and give it a fresh look.
Read on to learn how to stain over polyurethane without creating a sticky mess or spoiling its look.
What You’ll Need to Stain Over Polyurethane
Here are the supplies you need to collect before you start staining your finished piece of furniture:
- Gel stains
- Natural bristle brush
- Foam applicator
- Lint-free cotton cloth
- Fine-grit sandpaper
- Protective garments (Rubber gloves and nose mask)
- Tack cloth
- Scouring pad
Things to Consider When Staining Over Polyurethane
Before we dive into staining over polyurethane, here are some factors you need to keep in mind so that you don’t create a mess during staining:
- Use a darker stain color.
Since staining over already stained and finished wood won’t produce perfect results, consider buying a stain that’s darker in color than the finished wood color.
Darker stain color will help hide the imperfections and leave your furniture looking fresh and admirable.
- Follow the direction of the grain.
When staining over the finish coat, always work in the grain direction to maintain the wood grain pattern and avoid contrasting grain marks.
- Enhance stain adherence.
Since standard stain would not stick on finished wood, use gel stain or a combination of stain and poly. Also, light-sand the surface of your furniture to enhance stain adherence.
Step-By-Step Guide on Using Gel Stains Over Polyurethane
Once you’ve gathered all your supplies and prepared your workstation, it’s time to start staining. First, put on your protective gear and cover the floor with a tack cloth or plastic sheeting to protect it from stain spillages.
When you’re ready to start staining, follow these steps to stain your furniture and achieve an excellent finish.
Step 1: Clean the wood surface
Start by cleaning the furniture to remove dirt, grease, and debris from the wood surface. You can clean it using a solution of denatured alcohol or warm water with a few drops of dishwashing detergent.
Damp a scoring pad with the cleaning solution and use it to scrub the finished wood surface gently. Next, dampen a cotton cloth in warm water and use it to wipe the surface to remove traces of the cleaning agent. Leave the wood for about an hour to dry before proceeding.
Step 2: Sand lightly to smoothen the surface
Once it’s clean and dry, use fine-grain sandpaper to sand the wood surface lightly. This will help de-gloss the surface to enhance adherence to the stain.
A hand sanding sponge will do if you’re staining a small surface. However, consider an orbital sander if you are working on a large project. Remember to sand in the direction of the wood grain to achieve the best results.
Step 3: Wipe off the sawdust
After sanding, remove the sawdust and other residues by wiping the surface using a damp, lint-free cotton cloth. Failing to remove the residues will make the wood look untidy and unevenly stained.
Step 4: Apply your stain and let it dry
Once your wood is clean and ready for staining, use your natural bristle paint brush or a foam brush to apply a coat of gel stain evenly throughout the surface.
Work along the direction of the grain and ensure you cover the entire surface with the stain.
Use a lint-free cotton cloth to wipe off the excess stain and distribute it evenly on the wood surface.
Let it dry for about two hours, then apply another coat if you want your stained furniture to have a darker shade. Let your furniture stay in a well-ventilated place for 24-48 hours to dry completely. The longer it takes to dry, the better the outcome.
Step 5: Seal with a clear coat.
After drying completely, lock in the stain color by sealing the stained surface with a clear finish coat.
You can use polyurethane, shellac, or lacquer according to your preferences. The clear seal will protect the stained wood and make it durable, long-lasting, and resistant to wear and tear.
How to Stain Over Polyurethane Using Minwax Polyshades
Another alternative to staining over polyurethane with gel stains is using a combination of polyurethane and standard wood stain. The good thing is that you don’t need to go through the hassle of preparing your own blend.
You can buy Minwax Polyshades, a ready-made mixture of wood stains and polyurethane finish. Once you have your poly-stain mixture, use the following procedure to stain your finished wood:
Step 1: Prepare the wood surface
Start by cleaning the wood surface using warm water and a mild detergent to degrease and remove any dirt particles.
After cleaning, let it dry before sanding lightly using fine-grit sandpaper. Next, wipe off the sawdust using a damp cotton rag and leave it to dry.
Step 2: Apply a coat of Minwax Polyshades and let it dry
When the surface is dry, use a mixing stick to stir the Minwax Polyshade before applying it to your wood.
Use your paintbrush to apply a thin layer and spread it evenly on the entire wood surface. Stain in the wood grain direction and leave it in the open for at least six hours to dry.
Step 3: Apply a second coat to make it darker
If you want a darker shade, apply two or more coats until you get the shade you want. Be sure to leave enough drying time between coats for the best results.
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FAQs On Staining Over Polyurethane
Will polyurethane darken stain?
Water-based polyurethane is clear and will not significantly affect the stain color. Clear finishes have no color pigments that can darken the wood stain. However, oil-based polyurethane has an amber tint which can slightly darken your wood stain.
Can you stain over varnished wood without sanding?
Staining over varnished wood without sanding may not produce the best results. Sanding helps to de-gloss the varnish and increase adherence of wood stain onto it.
What finish can go over polyurethane?
Minwax Polyshades, which is a mixture of wood stain and polyurethane, can go over polyurethane finish perfectly. This is because polyurethane on the wood and the one on the stain bond to form a fresh coat of finish on the wood.
Do you have to remove polyurethane before staining?
No. You don’t have to remove polyurethane before staining. You can stain over an old polyurethane finish using a gel stain, which does not need to penetrate wood pores to stain wood.
Final Thoughts on Staining Over Polyurethane
If your furniture requires retouching, you don’t need to undergo the hassle of stripping the old polyurethane finish.
With just a little sanding and a few coats of gel stain, you can stain over polyurethane to give your wooden furniture a fresh look.
Did you find this tutorial helpful? Let’s know what you think in the comments. Also, feel free to share this article with your fellow DIY woodworkers to let them know how to stain over polyurethane without creating a mess.