How To Get Bubbles Out Of Dried Polyurethane – Best Solution For You

The bubbles on the dried polyurethane attached to wood products decrease their probabilities to become a perfect product. Though paying great attention to the producing process, on the last step of covering the wood with polyurethane, there come bubbles that destroy your satisfaction. There’s no need to be worried anymore. Scroll down for more information on how to get bubbles out of dried polyurethane. 

How To Get Bubbles Out Of Dried Polyurethane

Getting to know the roots of the trees is always best to assist the growing process. It’s only more efficient to learn the main reason that causes bubbles to appear on the dried polyurethane. 

Not many people truly understand where they come from and therefore are unaware of how to fix it. There are three common reasons: painting with the wrong brushes, improper preparation, and lack of cans shaking before application. 

Painting With The Wrong Brushes

The appropriate tool will result in the best product. You must select the right brush for the type of polyurethane you want to use to get a high-quality finished product.

Painting oil-based polyurethane requires a natural bristles brush  (produced from animal hair). They transfer a lot of the polish to the surface and help it last longer.  In addition, synthetic/nylon bristle brushes function well with water-based polyurethane.

When you use polyurethane with a water base on brushes with natural bristles, they will stick together and lose their form, making them more prone and creating brush marks.

Improper Preparation

To eliminate air bubbles trapped between the bristles and in the ferrule, wet your brush in a solvent before applying polyurethane to your prepared surface.

Soak your brush in mineral oils or water (respectively for water-based polyurethane or for oil-based polyurethane). Doing this will soften the bristles and deliver a better application.

How To Get Bubbles Out Of Dried Polyurethane

After that, remove the brush and gently squeeze off the solvent until air bubbles cease flowing out of the ferrule. You should also dry your brush by gently dragging it across an old newspaper, then start your painting art as usual.

Lack of Cans Shaking Before Application

The two most widely held (but unproven) myths among wood finish painters are that you should never shake the can or rub your brush down the side of the can to remove the excess substance. Both actions cause bubbles to develop in the poly, appearing on the surface after all the finishing touches.

#Step 1: Prepare proper Materials And Tools

Our project today requires sandpaper, foam roller or foam brush, and a stick of paint stir. Besides, it would be best to prepare a belt sander or mechanical sander, which is a useful tool to get rid of polyurethane bubbles. 

#Step 2: Sand The Polyurethane Bubbles Away

The first step in removing the polyurethane bubbles and preventing them from recurring is to sand them away.

A belt sander or a mechanical sander will come in handy since it will make this operation extremely simple, quick, and painless.

The process starts by using 320 grit sandpaper to sand the bubbles to get rid of them, and you won’t have to reapply both the polyurethane and the stain.

However, if the bubbles are significant, it may be worthwhile to sand off all polyurethane and start over.

In such cases, make sure to sand the rough polyurethane using 80 to 100 grit sandpaper to get rid of all the polyurethane.

How to get rid of bubbles on dried polyurethane

#Step 3: Stir The Polyurethane

Following up is to mix the polyurethane using a paint stir stick to remove the bubbles and prevent them from forming again.

If you follow this procedure, you will almost certainly avoid getting bubbles in polyurethane, as this is one of the most common sources of the dreaded bubbles!

A simple action of shaking the can may completely derail an otherwise excellent DIY effort. By shaking the can, little air bubbles will occur as you shake the can, and they will show up all over your lovely creation.

#Step 4: Using A Foam Brush To Apply Polyurethane

Applying polyurethane using a foam brush or foam roller is the next step in getting rid of polyurethane bubbles and avoiding them in the future.

As mentioned before, the type of polyurethane brush you use may make a big difference in whether or not you will have bubbles in your finished product.

On flat surfaces, foam rollers or foam brushes are the ideal applicators for polyurethane. They are inexpensive and can surely provide a flawless finish to your job. Unlike some other brushes, which may leave brush traces, this one does not.

#Step 5: Let The Polyurethane Dry In A Dust-free Environment

Allowing the polyurethane to cure in a dust-free and bug-free atmosphere is a must.

It’s common sense that if externalities get into your smooth outcome, they can cause bubbles and ruin your product.

For most DIY projects, polyurethane with Varathane Ultimate Interior Oil-Based is what we highly recommend using. Before recoating your product, let it dry for about 4 hours.

#Step 6: Apply From Two To Three Coats 

Just like how people are painting their nails, making them stable and smooth, you should apply at least two or three coats. 

Though the container says that it’s best to apply three polyurethane coats, two application rounds are sufficient. By doing this, each application of additional polyurethane improves the smoothness of your product.

Most importantly, each subsequent coat offers another layer of defense. This step is especially important for initiatives that are likely to be damaged, such as tables, chairs, or hardwood floors.

Final Thoughts

After reading through our “How to get bubbles out of dried polyurethane?” article, you should have enough information on what causes bubbles on your dried polyurethane and how to fix it. Now you won’t panic after greeting these little bubbles anymore. Make sure to follow our guidelines for a perfect finished coating.

Reference Source: How to Rub Out Your Polyurethane Finish

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