Once you’re done working on a wooden project, it’s obvious you want to see it shiny, and a polyurethane finish is what you need. The finish brings out a wood’s natural grain and beauty, keeping it safe from scratches. This guide on how to apply polyurethane will help you get the best results from your wood project.
Explaining 3 Methods of Applying Polyurethane
Wiping is the most common method of applying polyurethane. It simply involves using the finish with a clean and lint-free piece of cloth. You only need to wipe off the excess and leave your wood shining. The good thing with the method is thinness, as you can apply ultra-thin coats leading to less build-up in crannies and nooks.
When it comes to brushing, you need to make sure you get a fine and bristle-free brush. Avoid getting cheaper brushes, and they may leave strokes behind, affecting the wood’s appearance. When brushing, you only need to brush parallel to the wood grain to avoid strokes appearance. Complete every section with long and straight strokes. Make sure you brush out more bubbles as you can.
Spraying is the easiest yet effective way of applying finish to the wood. For best results, apply spray poly on a thin topcoat on top of a conventional polyurethane base. Once you do so, you will get a smooth finish without strokes appearance. The spraying method is an ideal solution, especially when dealing with tricky applications like vertical or fine detail surfaces. Many love this way since it reduces build-up and drips.
How to Apply Poly to Wood – Follow the Easy Steps
1. Sand the Surface
For better results, the first step should be to sand the wood surface to make it smooth. Sandpaper is the ideal material for this.
2. Remove the dust
Once your wood is smooth, eliminate the dust by wiping down the surface with a clean and dry rag.
3. Seal the surface
You can seal the surface by thinning the oil-based polyurethane with two polyurethane parts and a single mineral spirit. Brush the sealer with long and even strokes making sure you catch every run. Maintain a wet edge via overlapping every pass until you fully coat the surface.
4. Applying the first polyurethane coat
Once you seal, apply the first coat of finish spreading it over the entire wood with long and even brush strokes. Try to overlap the stroke for an even coating.
5. Shaving off the bumps
When the wood surface is arid, cut off any drips with a razor. The step helps in getting a smooth-looking surface.
6. Wet sand your first coat
Once the first coat is dry, usually within 24 hours, you can eliminate the blemishes if you wet-sand it with 400 grit sandpaper. You need to dip the sandpaper in water and run it on the wood in a circular motion to remove any dirt or bump. When it feels smooth, the surface should be wiped with a wet rag and a clean, dry rag.
7. Time to apply the second coat
You need to apply the second coat within 24 to 48 hours from the day you applied the first coat. Use the same procedure on the first coat to apply the second and final coat.
8. Repeat the steps in number 5 and 6 if needed
As soon as the second coat dries, remove the bumps and wet sand the surface with wet sandpaper.
9. Polish the surface
If you wet sanded the second coat, wait for about 48 hours before you can polish the surface. Dip a clean rag in water and apply the rubbing product to the surface in a circular motion. Once the surface gets dry, buff it with a clean and dry rag for a shinier and smooth finish.
Oil & Water Finishes – Do They Require Different Applications?
When using water or oil finishes, the result is somehow different, but the application is usually the same except in few aspects. The difference mainly lies in the time the finish takes to dry up and the time it takes before applying the second coat.
Generally, water finishes are clear and rarely alter your wood appearance. These finishes are also thinner, dry quickly, and emit less smell compared to oil finishes. On the other hand, oil finishes can pose a danger to the applicator’s health because of their flammability and higher VOCs if not cared for properly.
When cleaning up after the application, you only need soap and water for water-based solutions, but the oil-based options will be a bit heftier.
Solving Polyurethane Finishing Problems
When the finish fails to dry
Whether the drying issue falls with the wood or the finish, the ideal solution is to begin from scratch. Remove the finish with a mineral spirit and then wipe it off with denatured alcohol. Apply a coat of a universal sanding sealer and leave it for about 6 hours. After the 6 hours, apply the finish.
What if there are bubbles in the finish?
In case of any bubbles in the finish, the solution is to leave the finish completely dry. Once dry, sand the finish level using sandpaper and then apply another coat.
In an instance where the finish blushes, the sure bet is leaving it to completely dry. Once dry, sand it before applying another layer. It is advisable to add a coat that is 10 percent thinner than the first two coats.
Drips run or sags
The easiest way to fix the finishing flubs is to use a strategy that prevents the issues from occurring. When staining, try to apply the finish from the bottom up, so the drip falls on an already stained surface. When you drip a stain, it’s advisable not to attend to it right away. Doing so makes it look like a dark stained spot once you finish working on the wood.
Pros and Cons of Applying Polyurethane on Wood
Polyurethane offers a great shine making inexpensive furniture look posh without spending too much money.
The finish offers better protection to the wood since it’s among the hardest and durable finishes in this industry. Many use polyurethane when treating worn surfaces. It also protects the wood from daily scratches and spills.
Easy to apply
Besides being a protective wood finish, its application is not complicated, provided you follow the guidelines.
Unlike most polishes, you need to apply polyurethane on individual coats. It means you will take longer to finish, especially when dealing with bigger projects.
Polyurethane involves a longer drying process before you apply the next coat.
Not the safest
You need to apply the finish in a well-ventilated area since the product is toxic when inhaled, except for the water-generated options. Polyurethane is also flammable when it’s in liquid form.
Everyone wishes to keep their furniture safe and shiny. While not all finishes will offer the ideal results, polyurethane never disappoints. The process may seem long, but you will notice it’s a great DIY thing once you get it right. Make good use of this wonderful product and give your furniture a new and appealing look.