Can You Spray Polyurethane? (Yes! Here’s How To Do It)

Are you disappointed seeing roller fibers or brush marks on the final polyurethane spray coat after a flawless finish? 

That makes you wonder: since spray paint provides a smooth finish, wouldn't the same apply for polyurethane paint?

So, the natural question to ask is can you spray polyurethane? Read on to find out!

Before we answer questions like can you spray polyurethanes or how to spray polyurethane, let us first understand what it is and its uses.

Technically speaking, polyurethane is a plastic that can exist in multiple forms [1]. It can be customized to be either flexible or rigid and is also the material of choice for a wide variety of end-user applications like: 

  • Freezers and refrigerators insulation 
  • Furniture cushioning 
  • Insulation building 
  • Coatings 
  • Mattresses 
  • Adhesives 
  • Car parts 
  • Composite wood panels 
  • Sportswear 
  • Shoe soles 
  • Tires and rollers 

Polyurethanes are modern, safe, and versatile.

They are used in various applications to create all kinds of industrial and consumer products, which play a critical role in making our lives more comfortable, environmentally friendly, and convenient.  

If you want to filter the polyurethane, use a mesh filter or some old pantyhose.

Polyurethane Spray

It is better to spraying polyurethane because it needs no specific technique.

Moreover, using paint sprayers for polyurethane for spraying provides a stunning finish polyurethane topcoat or final coat which further enhances anything from furniture to floors and cabinets. 

Furthermore, best paint sprayer like yattich paint sprayer improves the durability of wooden surface.  

Another popular question that people looking to spray paint polyurethane ask is whether you can spray polyurethane with an airless paint sprayer, a traditional spray gun, or an HVLP sprayer. You can. 

Airless sprayers are the best choice for the highest yield. Following through with a long, continuous movement is really important .

Furthermore, HVLP sprayer guns will also be cost-efficient. HVLP spray gun help you apply polyurethane and other thin coatings exceptionally well. This also holds true for traditional spray guns. You can dilute and wash away water-based polyurethane spray with gun cleaning solvent.  

Now that we have understood the answer to the question, can you spray polyurethane with spray gun? 

The next thing that acts as a dilemma for multiple individuals is can you spray water-based polyurethane and can you spray oil-based polyurethane? So, here's the difference between the two and whether you can spray both coating variations.  

There is no doubt that water-based polyurethane is much more transparent than oil based products like oil based poly counterpart.

It forms fewer inflammable organic compounds and spraying polyurethane toxic fumes than oil based polyurethane takes, and it is a much better and eco-friendly alternative. Unfortunately, though, one disadvantage of using water-based coating is lower durability [2].  

On the other hand, using oil-based polyurethane to next coat DIY furniture brings out a great look, a feat that water-based polyurethane cannot achieve. 

Furthermore, you can also spraying polyurethane on wood; the oil-based polyurethanes typically increase the darker woods' color, whereas the water based poly are greater for lighter woods. To learn more about how to spray polyurethane on wood, watch this video guide.  

Another question that arises most is, can Minwax fast drying polyurethane be sprayed? Well, having polyurethane in a spray can in aerosol polyurethane does provide great convenience. 

This product can spray over wood finishings and furniture, making home renovation and DIY projects management relatively easier.  

You will get an extremely robust protective polyurethane coating when you spray MINWAX polyurethane over wood. It can also be sprayed over paint, unfinished or finished wood surfaces, and is predominantly used over various types of wood.

It is a multipurpose polyurethane spray since it adds long-lasting protection, but it also increases the underneath wood's natural beauty due to its shiny and precise finish.  

You can spray all kinds of unfinished wooden surfaces and paint them with polyurethane spray. This finish's product is attractive, long-lasting, and durable.  

If the air bubbles are trapped inside, it can be a huge problem because they never leave even after the application of polyurethane coatings.


How To Spray Polyurethane Step By Step

Now that we have agreed that you can use a spray to apply polyurethane, you must know the required steps to follow to ensure you know how to use spraying polyurethane and its process. These are the following steps you must abide by: 

  • 1
    Prepare The Working Area 
    To prepare to spray or foam brush polyurethane formula, the initial thing you must do is to set up the work area. Typically, polyurethane has low levels of toxins, and the chemicals, when exposed to things such as vegetation, can be harmful. 

    That is why when you are preparing your working area, make sure to cover all the plants within the vicinity, and if you are working indoors in a room, ensure proper air circulation so you do not inhale toxic fumes from the polyurethane compounds.  
  • 2
    Surface Preparation 
    Once you have prepared the working area, it is better to shift your attention to preparing the surface you wish to apply the polyurethane finish. First, clear the surface to remove any dirt and grease.

    Your formula will easily stick to clean surfaces, making sure that you get the best possible finish. You can also use water and soap to clean the wood surface, particularly if it is bare wood.  
  • 3
    Polyurethane For Spraying  
    Now you are ready to spray, but before starting with the procedure, make sure the materials you will employ for this task are ready as needed. Polyurethane application, especially when you use a sprayer, requires you to thin it.
    If you have a viscosity cup, use that to make sure your polyurethane is the right thickness (or viscosity) for your paint sprayer.
    However, there are some formulas of thin polyurethane that do not require thinning polyurethane. That is why we recommend that you initially spray the formula without using a paint thinner to thin polyurethane and observe the finish you get during this process. 

    Once you are confident that the formula is correct and ready for application on a wooden surface, go through with the application. Apply in thin polyurethane coats to provide an excellent finish and a smoother feel. 
    You can also apply two to three additional thinner coats of thin polyurethane until you get the spray patterns you desire.  The vertical spray pattern is perfect for spraying vertical surfaces like table legs .
    How Can You Thin Polyurethane? There are various products that you can use to thin polyurethane for multiple thin coats. This should depend on the type of polyurethane used. Some products include mineral spirits, turpentine, paint thinner, or even just water. Over-thinned polyurethane never provides what real polyurethane gives to your woodworks or furniture. To prevent over-thinning, you should use polyurethane to mineral spirit ratio of 4 parts of polyurethane to one part of mineral spirit (4:1).
  • 4
    Cleaning And Drying Process Of The Finish 
    Once you have successfully applied the polyurethane formula, you must allow it to dry completely. According to the formula used, the drying time of your polyurethane varies.

    For example, an oil-based polyurethane can take around twenty-four hours to dry, whereas thin water based polyurethane spray counterpart only requires four hours to dry to touch or even walk over in case you were applying polyurethane to the floor.  

Tips For Spraying Polyurethane

When you are looking for the best ways to spray polyurethane, here are some tips and essential things you must remember while employing spray or brush polyurethane:  

  • If you can, always make sure that you are wearing a fume or chemical resistant mask to avoid fume inhalation
  • In the case of your spraying poly formula to the vertical surface, make sure that you are careful to steer clear of drips and runs
  • Make sure that you always apply a thin coat (first coat) on the application surface for a quicker polyurethane dries to give it a best possible finish
  • If you experience some runs in the polyurethane application process, ensure that you have taken additional precautions, so it does not affect your coating work
  • To get a clean finish, use a razor blade; it can remove runs more efficiently
  • Put all the safety measures in order before starting the whole process of polyurethane for spraying. When working with polyurethane, it's important to wear protective gear to avoid getting the toxic volatile organic compounds (VOCs) and isocyanates in your eyes, nose, or mouth.
  • The green tip sprays latex paint, chalk paint and milk paint in a 1″-6″ spray pattern which is also great for furniture projects.
  • Eagerly stay on application angles, so you get the best possible finish on the surfaces, like wooden floors 

Room Painted with Polyurethane

Frequently Asked Spraying Polyurethane Questions

Can you spray paint and lacquer over polyurethane? 

No, you cannot spray polyurethane over lacquer since it will most possibly not bond to it. The polyurethane coat will flake and peel over time if you do it nonetheless.  


How long does spray polyurethane take to dry? 

Spray polyurethane will be dry to touch within the two hours of the application process. At this moment, you can add a second and third coat easily. 


Can you buy polyurethane in a spray can? 

Yes, there are multiple spray can polyurethanes on the market. They can either come in an accessible spray can form, or they can be loaded inside a paint sprayer.


Is it better to spray or brush polyurethane? 

Every kind of polyurethane formula has its preferred applicator, usually drop cloth or tack cloth or brush. Certain polys are also available in aerosol spray cans. The brush-on polyurethanes work the best on flatter surfaces, where it is essential to create a durable film. Sprays hold a good finish, so you can cover a more extensive area every time you load them. 


Conclusion

Hopefully, this guide was able to help answer various questions such as can you spray polyurethane, how to spray oil-based polyurethane, and the best way to spray polyurethane.

Using a spray polyurethane provides a much better finish, and you can also apply multiple coats to get an excellent finish.  The three brass spray tips are reliable, and they are resistant to wear and corrosion as well.

References: 

1. https://www.polyurethanes.org/en/what-is-it/

2. https://www.valentiflooring.com/blog/oil-based-vs-water-based-polyurethane