Who doesn’t love to get a nicely coated kitchen table? But sometimes, a nicely coated kitchen table can be brittle. It means the coating needs to be tough as well. If you use professional coating elements like urethane, polyurethane, only then you will have a tough kitchen table.
However, while selecting the polyurethane, it is essential to decide the correct form of polyurethane. Because polyurethane is available in water-based and oil-based.
Depending on the type of wood and condition of the stairs, usually two or three coats of oil-based polyurethane are enough. However, you need to be aware that it takes longer to dry. Also, it can add an amber glow to the wood, making it susceptible to brush marks.
Polyurethane is a common finish that people use to protect their hardwood floors. It can also help make the wood look shiny and new. But how many coats of polyurethane for hardwood floors is just right? This blog post discusses two different types of poly, and how many coatings you should apply for each to get the best result.
What is a Polyurethane Coating?
Polyurethane is a substance that can either be water-based or oil-based. Oil-based polyurethane has been around for longer, and it is a form of alkyd varnish which is combined with polyurethane resin.
Alkyd is a substance found in basically any varnish or oil-based paint. By adding polyurethane resin to this, you get a much stronger and more resistant product. Thanks to the addition of polyurethane resin, this type of finish has excellent water, scratch, and heat resistance. Water-based polyurethane finishes are a combination of an acrylic resin with polyurethane.
These coatings are not as strong as the oil-based version, but they do offer a number of favorable properties.
There is another option available though. This is an oil0-modified water-based polyurethane. Basically, this substance offers the best of both worlds. It is quick to dry, safer to use with fewer chemicals, easy to clean while maintaining the durability of an oil-based product.
Types of Polyurethane Floor Finishes
There are two types of polyurethane that people can use on hardwood floors: water-based and oil-based.
Water-based polyurethane
Water-based polyurethane is a type of clear finish that provides a protective coating for wood. It’s easy to apply, and it dries quickly. It can be used on raw or finished wood surfaces, such as furniture, floors, doors and cabinets.
Unlike oil-based finishes which are more difficult to clean up after application, water-based poly is easier to clean off your hands when you’re done applying the product.
Oil-based polyurethane
Compared to water-based polyurethane, oil-based poly is more durable and can resist water, stains or scratches. But it’s also harder to work with because the smell is stronger and you’ll need to wear a mask for protection during application. Clean up is a bit tougher too as oil-based polyurethanes are difficult to clean off your hands once they’re dry.
Oil-based polyurethane is best suited for high traffic areas where durability matters most like staircases, hallways, kitchens and living rooms–places that see lots of wear from people walking on them day after day.
How Many Coats Of Polyurethane Are Needed To Achieve A Beautiful Finish
You will want to apply Polyurethane to your woodworking project to ensure it is properly finished and left looking shiny and new. Applying this substance will ensure a protective coat is added and the wood will last longer.
The question is not whether or not you should add this protective substance to your wood. That is a given. It is how many coats of Polyurethane are needed to achieve a beautiful finish.
1. Sand Your Wood
When wood is left unsanded, it is more porous and difficult to work with. No matter how many coats you add of Polyurethane, the look will still not be completed. Unsanded wood is hard, bumpy, and often unpleasing to the eye.
It is best to sand your wood before any coats are added. This ensures the protectant goes on smoothly and actually provides a finished look. You can use a belt sander on larger projects, or sandpaper by hand on smaller wood items.
If you are using a belt sander, it is best to stick to a fine grit. It is also wise to use a few different grit levels and multiple sanding times to ensure it is done properly. Start with 100-grit and work your way up to a 220-grit that provides extremely fine sanding.
2. Remove Wood Dust
After sanding, there is going to be a lot of wood dust left on your project. This dust needs to be removed if you want your Polyurethane coats to stick well. You can simply brush some of the dust off first, and then use a vacuum to get the rest.
A cloth that is lint-free also works well to remove dust from wood. The Microswipe cloth is a good option. It is designed with wood projects in mind.
The area where you are working should be free from dust as well. This is because you want the space to be as clean as possible so nothing contaminates the surface while you are allowing it to dry. Fully vacuum the area using a shop vac and dust off any surrounding surfaces.
It is also best to leave a window slightly open on one end, with a fan pointed outward on another end. This will help to improve the air circulation so you are not left to breathe in all of the chemicals from the compounds.
3. Oil-Based Vs. Water-Based
There are two main types of Polyurethane. The first is an oil-based option. The second is water-based.
The oil-based option is more common. It is easier to work with, but does take more time to dry. More coats of the substance are also needed to get the desired thickness level and finishing on the wood.
The water-based choice is mainly used for professionals. It takes a lot less dry time, and fewer coats, which makes it appealing to do-it-yourselfers.
4. 3 Coat Application
There needs to be 3 coats of Polyurethane applied, especially if you are using an oil-based finish. The first coat should be mixed with mineral spirits. This acts as a sealer and provides a barrier between the wood and the oil finish you are using.
A bristle brush is needed to apply the coats. Long, even strokes will ensure the entire surface gets covered. It is also best to wait a few minutes so you can blend in any run-off oil.
You should wait about 24 hours for the seal coat to dry before applying Polyurethane straight from the can. The same even strokes should be used for this coat. Once you think you are finished with one coat, go back over it, going with the grain only.
Wait another 24 hours for this coat to dry. Once that is complete, apply another undiluted coat of the Polyurethane. It should be applied in the same manner, first covering the wood, and then going with the grain only to complete the finish.
5. Fix Blemishes Before Adding a Final Coat
After approximately 12 hours, the coat should be dry enough for you to begin fixing blemishes. This includes using a razor to cut away any excess finish that is bubbled up on your wood. Be careful not to cut into the finish or wood, and only remove the bubbled up section.
Wait an additional 12 hours, and then go over the finish with sandpaper if needed. You should get the sandpaper wet in order to wet-sand the blemishes out. This will prevent you from going too far, unless you over sand.
If you need to sand out blemishes, a coat of polish needs to be applied. This should be done after 48 hours have passed. Use a rubbing compound first, and then follow up with a polishing compound.
A clean cotton cloth should be used for each of these applications. The cloth should be dampened with water before adding the rubbing compound. A dry cloth should be used once everything is dry to buff out any areas that need it.
Once all of this is done, you have a finished wood product that is as shiny and well-protected as a piece you would have purchased.
Useful Tips for Working With Polyurethane
- Always stir the polyurethane mixture instead of shaking it. This will help to prevent bubbles from forming.
- When using a brush to apply oil-based polyurethane, make sure that it is a quality natural bristle brush. This will help to avoid air bubbles as well as brush marks and streaks.
- Water-based polyurethane can be brushed on with synthetic brushes. If you use a foam or roller brush, bubbles can arise Thinning polyurethane can be done to achieve a faster drying time.
- The first coat should never be thinned though. Thinning polyurethane can be done for the base coat and other layers, but never the first coat as this affects how the polyurethane sticks to the wood.
- While brushing on the polyurethane, the brush should be kept damp with a solvent. By dipping it in something like mineral spirits or water (depending on the type of polyurethane), the brush becomes much easier to clean.
- Wiping the brush on the can of the polyurethane can result in bubbles. Rather tap any excess polyurethane off over the container.
FAQs
How Long Does Polyurethane Take to Dry?
Well, an oil-based polyurethane would require about 24 hours to dry. The water-based poly, on the other hand, needs just about 6 hours to dry to touch or to be ready for slight traffic (Click here for the details).
How Long Does it Take a Fast-Drying Polyurethane to Cure?
It will take up to 30 days for your polyurethane floor to cure; therefore, it would help if you allow the surface 30 days before you start putting the area rugs over the surface. If you are looking to have your rugs back a little sooner, you should give the surface for about 2 weeks; even so, 30 days is better.
Can I use a Foam Brush to Apply Polyurethane?
Yes, you can use a foam brush in the application of your polyurethane finish. Alternatively, you can choose to use a bristle brush that is about 2″ wide. Foam does a great job of eliminating the chore of cleaning because these brushes are affordable and thus disposable. You can apply the initial coat without diluting or choose to dilute with half the paint.