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Polyurethane offers a brilliant finish for a wide range of DIY projects. Many people get intimidated by using polyurethane, as this substance can offer challenges. However, once it cures, polyurethane is durable, clear, and offers a good looking finish for a wide range of surfaces. Using a polyurethane spray is always a good option, as it is easier to apply and it allows you to achieve a great even finish each time. If you are considering a polyurethane spray for your next project,m then be sure to check out our complete guide below.
Table of Contents
- 1 Why Choose a Polyurethane Spray?
- 2 How to Spray Polyurethane?
- 3 Spraying Polyurethane Guide
- 4 Getting the Polyurethane Spray Prepared
- 5 Choosing the Right Polyurethane Spray Paint
- 6 Using a Water-Based Polyurethane Spray
- 7 Frequently Asked Questions
Why Choose a Polyurethane Spray?
Polyurethane is already a delicate finish to try to apply. If you decide to paint it on with a brush, the application process only becomes more difficult. Spraying polyurethane allows you to achieve far more accurate results. When you paint polyurethane with a brush, there is a much greater chance of creating bubbles on the polyurethane surface. You also have to be incredibly careful when brushing, as there is always the possibility of leaving brush marks and bumps in the finish. You could also trap moisture in the polyurethane when brushing incorrectly which will result in a cloudy finish. Choosing to use polyurethane spray removes these difficulties. It allows you to apply even coatings over difficult to reach areas and strangely shaped contours. It also removes the risk of things like brush marks or strange surface textures. Spraying polyurethane will involve a couple of extra steps and probably more coatings than brushing it on. However, the end result will be superior.
How to Spray Polyurethane?
When you spray polyurethane, you get a far more enhanced finish when compared to brushing it on. However, spraying polyurethane will involve a more particular technique. Dont worry though, as this is easier to get right than using a brush. When starting to spray, hold the spray nozzle about 10 to 12 inches away from the surface of whatever you are coating. This will allow you to get a smoother, more even coat without any bumps or paint buildups. Then when you start to spray, maintain a steady flow. Do not stop halfway, as this will give you an uneven finish that will be tricky to fix. So, spray the entire surface area before you stop.
A good method to ensure evenness is to start spraying with the sprayer just pointed towards the air, then bringing it down to meet the surface. This way you won’t miss a patch and will get the same amount of polyurethane spread over the item.
Make sure to keep a stiff wrist while spraying. Waving it around will result in uneven waves and arcs forming instead of a straight line. This can lead to an oddly covered surface, with some patches being thicker than others, and some areas remaining exposed. Also, always keep a straight motion going when spraying. If you spray for too long in one area, it will result in a buildup of polyurethane which could cause drips or runs.
When you spray polyurethane, it is important to know which settings are best for which sections of the project. A good sprayer will be adjustable with a range of different settings, allowing you to change between them as you spray different areas. For example, a vertical setting should be used for spraying up and down things like table legs, columns, or pegs. Horizontal settings allow you to move the sprayer across larger areas, while the circular or middle setting is ideal for getting contours, corners, edges, and details.
Best Aerosol Polyurethane: MINWAX Polyurethane
Having a spray can polyurethane available in an aerosol form offers complete convenience. You can easily use this product to spray over furniture and wood finishings – making DIY and home renovation projects much easier to manage. When sprayed over wood, you get an extremely durable protective coating. It can be sprayed over finished or unfinished wooden surfaces and is suitable for use over a variety of wood types. This is a versatile polyurethane spray. Not only does it add a great layer of long-lasting protection, but it also enhances the natural beauty of the wood underneath thanks to its shiny clear finish.
Best Water-Based Polyurethane: RUST-OLEUM Varathane Ultimate Polyurethane
This is is a strong and versatile solution for all kinds of projects. Rust-Oleum, a well-respected brand, has created this finish to be scratch-resistant and anti-yellowing. This finish can be used over a range of indoor uses, including furniture, trims, doors, cabinets, and more. This polyurethane dries to a clear satin finish which makes it enhance the look of the wood underneath it. Thanks to its great clarity, this polyurethane can be sprayed over all types of wood. It is also a low odor formula, making it a safer and more suitable choice for indoor use.
Best Paint Sprayer: GRACO Ultra Max Cordless Airless Handheld Paint Sprayer
If you want to spray polyurethane, then you will need a great sprayer to get the job done properly. Using this airless sprayer by Graco offers ultimate convenience and ease of use. First of all, this is a cordless, airless sprayer. This means that you can use it anywhere without having to worry about plugs and power cables. However, this does not mean that the power or capacity is limited. This sprayer uses a Dewalt XR lithium-ion battery system that lasts long and charges fast.
- Perfect Airless Finish at Any Speed - Without Thinning
- Fully Repairable for Extended Life, Uses RAC X FFLP Spray Tips
- Sprays Water, Solvent, and Flammable Based Materials
From a single charge, you can spray up to 1 gallon of fluid. When using this sprayer, you get a perfect, smooth finish every time. This can be achieved with far greater efficiency in comparison to other models. It allows you to work faster and saves you time. This sprayer is a great choice for anyone that wants a device that is easy to carry around and travel with. The spray tip options are good, there are great adjustable settings, and the powerful battery will allow you to enjoy an excellent spraying experience.
Spraying Polyurethane Guide
If you want to spray a water based polyurethane or have a convenient aerosol spray can polyurethane, there are certain steps to take when applying it. Here is a simple tutorial on how best to use polyurethane spray.
The essential first step to any polyurethane spray project is preparation. This is crucial, as you won’t be able to achieve a long-lasting polyurethane finish if everything has been prepared properly. Start by sanding down the surface of the item you want to spray. Make sure that it is even and smooth, and that any gaps or holes have been sanded over. Clean and dry the area, making sure that there is no dust or dirt present. Then you can apply a stain over the surface. Wait for this to dry completely.
Spraying polyurethane needs to be done in an environment where no dust, dirt, or bugs will be present. Get the surface of the item you will spray completely clean and dust-free. If you spray the finish over any dust or dirt, it will affect the adhesion of the polyurethane, as well as trap that dust underneath the clear finish.
Choose the Right Spraying Tool
When setting up your sprayer, you will need to make sure that you have the right spray tip and setting. Generally, any 1 to 5-inch wide spray tip is perfect for polyurethane application. Most spray guns will have a variety of tips available to choose from. Once you have set up the right spray tip, you will need to get the spray volume adjusted to the right setting. Use the control knob to make sure enough polyurethane is released for a completely even coating. You can do a few test sprays on a random piece of wood or paper to make sure that the settings are correct.
Using the Right Spraying Technique
When you spray polyurethane, you need to follow a few guidelines to get the best results. Here are some useful spraying tips to follow:
- Maintain a long, steady movement while spraying. Dont start and stop, as this will cause dense areas of polyurethane in some places and less coated areas in others
- Keeping a continuous movement also helps to prevent runs and drips
- Keep a firm wrist while spraying in order to maintain a uniform and thick coat
- Always consider the different spray patterns available, as you should adjust these based on how and what you are spraying
Leaving the Finish to Dry
Once you have finished applying the polyurethane coating, you can leave the finish to dry. Then, only when it is completely dried, you can give the surface a good clean. This can be done simply with some gentle soap and water. Just check out the manufacturer’s guidelines, as different products have different drying times. If you are working with a water based polyurethane spray, it will have a much faster drying time than an oil-based one.
Getting the Polyurethane Spray Prepared
Whenever you use a sprayer, you need to make sure that the consistency of the substance you spray is correct. Polyurethane has a slightly thicker consistency, so it may need to be thinned down a bit to use in a spray gun. Start by trying to spray the polyurethane without thinning it, but if you get a kind of orange peel finish, or large clots coming through, then you will probably need to thin it out. Adding thinner also helps to get the polyurethane to flow nicely from the fluid nozzle when using a gravity feeder. If it isn’t flowing properly, the polyurethane is too thick. If the polyurethane still isn’t spraying properly, you could also try to adjust the pressure settings to a higher level.
If you do add a thinner, make sure to get the ratio correct with regards to the polyurethane. Polyurethane products should come with a reference sheet to help guide this. Usually, you will be looking at adding around 10% thinner to prepare the polyurethane for spraying. This can differ between products though.
Choosing the Right Polyurethane Spray Paint
Spraying polyurethane will only really work well if you choose the right product for your specific application. As there are various polyurethane options, you will need to make sure that you choose the right one for your project.
Water Or Oil Based?
Should you spray water based polyurethane or is it better to use oil-based polyurethane? This is one of the first questions to consider. Both types work well in their own ways and offer unique pros and cons. Both types are very durable and offer a great looking surfaces finish, however, there are some critical differences between them.
If you spray water based polyurethane, the drying time is much quicker than with oil-based products. Try to choose one that works best for your needs and work. When using a water based polyurethane spray, the finish should dry in about 2 hours. You can then apply the next coat. Oil-based polyurethane dries in about 5 to 12 hours. There will also be fumes around while drying. Water based products are safer and dont emit the same kind of fumes that oil-based products do.
The finished effect of the polyurethane is the next consideration. Water-based polyurethane does not provide the same kind of dark shiny glow that you get from oil-based products. Water-based polyurethane only really gets a great finish from the final coating, while oil based products require fewer coats due to a better finish with each coat. When it comes to finish, most people prefer oil-based polyurethane.
Using a Water-Based Polyurethane Spray
Using a water based polyurethane spray compared to one that is solvent-based offers a range of benefits. First of all, there is less of a fire risk associated with water-based products. The fumes are much safer and vastly reduced. Water-based products are also safer to use and more environmentally friendly. However, water-based polyurethane is more challenging to apply.
While the spraying process remains pretty much the same, there are still some noticeable differences when using water-based polyurethane. We have offered some solutions to these issues below.
- You will need to be careful to avoid creating any stains on the surface before you start spraying. Being diligent is important when working with water-based polyurethane
- Water-based finishes dont atomize as well when being sprayed. Using an airless or air-assisted sprayer will help to improve this during the application of water-based polyurethane
- Pay close attention to how you prepare the surfaces for spraying. Make sure to properly sand the surface, and sand the first layer in order for the second coat to adhere properly
- Water-based polyurethane finishes dry faster than oil-based ones. You can influence the drying time by changing the heat or airflow in the working environment
- When spraying a water-based polyurethane, cleaning up can be a tricky process. You will need to take apart the spray gun and clean each individual part. Using a gun cleaning solvent is a practical solution for this
Once you have finished spraying water-based polyurethane, you will most likely have to do a few touch-ups. The final finish is the coat that really provides durability and shine. Oil-based polyurethane offers a superior quality of coating and shine from the first coat to the last.
Frequently Asked Questions
Should You Spray or Paint on Polyurethane?
Spraying polyurethane allows you to get a more precise and even coat. Many polyurethanes are available in spray cans. Brushing the polyurethane on is good for large flat surfaces, and provides a thicker coat. However, you will not get the same level of smoothness over the surface compared to when you spray.
Must You Thin Polyurethane to Spray it?
Polyurethane is a thicker substance, so it generally requires thinning before being used in a spray gun. Try spraying it without thinning first to see if it requires thinning. This differs between brands and products.
Can Minwax Polyurethane Be Sprayed?
Minwax polyurethane can be sprayed. However, there are also plenty of other polyurethane finishes that are more specifically designed for spraying.
Can Polyurethane Be Used in an Airless Sprayer?
Yes, most regular paint sprayers can be used with polyurethane, including airless versions. Just be sure that the sprayer is completely cleaned out between uses, and that the polyurethane is the right viscosity.
How Can You Thin Polyurethane?
There are various products that you can use to thin polyurethane. This should depend on the type of polyurethane used. Some products include mineral spirits, turpentine, paint thinner, or even just water.
Do You Get Spray Polyurethane?
Yes, there are various spray polyurethanes available. Polyurethane can come in a convenient spray can form, or be loaded into a paint sprayer.
Polyurethane spray provides a fantastic finish to all kinds of wooden surfaces. This finish is durable, attractive, and long-lasting. If you are thinking about using polyurethane, then be sure to consider spraying it for great results.