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We’ve all experienced the pain of trying to clean dried paint off of a paint brush, but what about trying to clean dried polyurethane from a paint brush?
Getting anything off of a paint brush once dried is a tedious and irritating task, but polyurethane can really make everything more difficult.
No worries though, we’ve got your back and will help you understand how to clean up your brush step by step, without making a mess or getting frustrated, because we all know how difficult it can be to get anything out of the fine bristles of any brush.
So, to make sure that you learn how to get polyurethane out of the bristles of your paint brush, we will discuss a few things with you today, including what you will need to know about doing this before you get started, what things you will need to do this, and the steps that are required in order to completely get the polyurethane off your brush for good.
Things that you should know about cleaning dried polyurethane from a brush
No matter what you are using your brush for, or whether you use acrylic paint, oil paints, housing paints, or polyurethane, keeping your brushes clean is an essential part of brush maintenance, so that your brushes keep their quality long term.
You see, all brush bristles deserve some tender loving care. They do a lot of the hard work for you, and are interacting with all those chemicals in the paints that you use, some of these chemicals are not super friendly either.
This means that regardless of whether or not they are natural and real hair, or synthetic hair, they still need to be maintained to retain their quality year after year, project after project, no matter what you use them for, and how often they are used.
One of the biggest parts of this is having a good clean up technique that will assist you clean your brushes with love and care straight away, or at least as quickly as you can, so that the paint does not have the opportunity to turn hard and ruin your brush long term, granted brushes can be salvaged from hard paint, but avoiding it is often the best way to go about saving them.
If your brush does have polyurethane stuck on it then do not worry, it can still be salvaged, and you can store them in no time at all with just some simple steps. But, let’s not get ahead of ourselves just yet.
Gently does it
Before we get into telling you about how you should actually clean your brushes, and your brush bristles, we should tell you to combat them.
Any high quality brush deserves much quality care and attention, and this is not just because you should treat your nice things with love, but it also because being gentle and loving with those bristles will actually contribute further to the longevity of your paint brush.
And in many cases this does not just apply to high quality brushes, but really it applies to any.
Why is this? This is all because of glue. Yes, glue. You see, those bristles are actually glued into the part of the paintbrush which is called the ferrule, or what you will see as the metal bracket just below the bristles that hold these bristles in their places.
If you dive in hardcore, giving those hardened bristles a vigorous scrubbing, you run the risk of pulling some of those bristles out of place and affecting the quality of your brush.
Although losing a few bristles here and there is not the end of the world, it does have the potential to add up over time, and if it keeps on happening then you may be left with only a few pitiful strands that won’t really do very much.
When you are working with any decent brush, it is imperative to maintain their quality and their bristles for as long as you possibly can.
Synthetic brushes Vs Natural brushes
There are plenty of techniques that will apply to either synthetic or natural haired bristles, but there are some things that it is worth noting down before you get cleaning.
The most important one is that natural hair bristles need to be treated with even more care and even more gently than synthetic bristles do.
This is simply because they are much more likely to suffer a permanent breakage, just because they are natural. Think of the hairs of your head or body vs the hairs of a wig, it’s a similar concept.
Real hair will break, whereas synthetic bristles can be bent back into place should they start to get a bit wonky. A natural hair with a bend, will stay that way forever. So whatever amount of care you are already thinking of providing for your bristles, you should double it for natural bristles.
Knowing this, it is easy to feel a bit discouraged, regardless of the type of bristles that you are working with. But, do not worry, we will give you our best tip-top DIY tips for getting dried paint off of your brushes so that you can get back to painting well with no problems.
Cleaning polyurethane off of your brush means you will be working with some harsh chemicals, such as paint thinner when you are cleaning your brushes.
These chemicals are highly caustic and can be very bad for your health if you do not take the proper precautions when it comes to handling them appropriately, much like polyurethane paints or shellac, or indeed any other oil based paints or solutions.
It is very important that you only work in a well ventilated area while you work with these chemicals, try to keep windows open, and ventilation systems on. You should also use gloves, goggles, and ventilated masks when you are working in direct contact with any of these things.
These solvents can cause severe health problems should they be inhaled, ingested, or even absorbed through skin, so be cautious, be careful, and handle them safely.
What supplies will you need?
When you are going to clean any brush, it is very important to remember that there are some key things that you will need to get the paint off, especially if it is dried, it is not always as easy as hot water and some soap. Not when it comes to natural bristles, or dried paint. It is always best to use proper supplies.
You may not need to pop to the store to do this either, there is a chance that you will already have a few of them in your home already, and then you will only need the others if the dried up paint is too stubborn and simply refuses to come off with your basic cleaning methods and supplies.
So, what do you need?
- A brush comb.
- Some paper towels.
- Two glass, or plastic containers.
- A plastic bag.
- Mineral spirits.
Some people may recommend using a few other cleaning methods that will involve a fabric softener or other general household cleaning supplies to soften up your brush.
But, the issue with this, is that when you are using an oil-based paint such as polyurethane, you cannot trust in soap to remove the paint, and you can’t just wash the runoff down the drain as these chemicals are fairly toxic, and they simply are not meant to be entering the sewer system.
So for this method of cleaning, we recommend that you use mineral spirits, which are the definite best way to remove oil-based paints. You can get mineral spirits pretty easily, you can find them at your local hardware stores, at Lowes, or you can buy them online at Amazon.com too.
How to Guide: softening up a hard brush
Do you have everything at the ready? It is time to soften up that hard paint brush and bring those beautiful bristles back to life!
Let’s take a quick look at what these steps are, and then we will go into more detail about them.
- Use a paper towel to remove what you can of the polyurethane.
- Get a container, and put the mineral spirits into the container.
- Place your brush into the container with the mineral spirits.
- Transfer the dirty mineral spirits.
- Repeat the process as many times as needed if needed.
- Brush off your brush with hot water.
- Dry brush with a paper towel.
Now we know the process, let’s take a look at how we can go about cleaning up your brushes.
1. Using a paper towel
The first thing that you need to do is take some mineral spirits and saturate a small section of your paper towel.
(You could use a paint thinner or a lacquer thinner for this if you do not have any mineral spirits. However, these solvents could strip the brush or damage it, so it is recommended to use mineral spirits if you can)
You are going to use this to try and saturate some bristles of your brush and remove some excess polyurethane before you soak it. If you can remove a fair bit of it, it can make the later stages easier to complete.
Cleaning off what you can with the saturated paper towel can kick-start the process and lower the amount of polyurethane that you will need to tackle in the overnight soak. It will leave your brush much cleaner after just one soak and minimize the amount of work and waiting you will need to do in the long run.
Be sure to use gloves to do this though, you do not want to get any mineral spirits on your hands as this can be damaging to you and to your health. You should also make sure that you do this in a well ventilated area.
2. Mineral spirits
Now it is time to use up the major part of the mineral spirits. Get your first container and fill it up with the mineral spirits. Fill it to a level that allows you to place the bristles into the container and have them saturated.
You may want to measure this to ensure that you are only soaking the part of the bristles that are coated with the dried polyurethane. You will want to avoid the ferrule, which is the metal part of the brush, from touching the mineral spirits even slightly if you can.
3. Brush meets mineral spirits
Now it is time for us to place the brush into the container that you have filled up with the relevant amount of mineral spirits. This part is pretty easy and pretty self-explanatory as well really.
Simply make sure to swirl the brush around for a bit in order to agitate the solvent and allow it to penetrate into the bristles for a maximum cleaning power.
Once you have done this you can just leave the brush in its container for several hours, or even overnight. We recommend overnight for the best results though.
It also depends on how much polyurethane you are dealing with. If there is a lot of dried polyurethane on your bristles, you may need to let it sit a bit longer. However, generally, leaving it to soak overnight will do the trick, but it is best for you to make your own judgement based on what state the brush is in
4. Transferring dirty mineral spirits
Once your brush has sat in its soak for a while, take your container with those dirty mineral spirits and transfer it into a container for disposal. As mineral spirits, paint thinner, and oil paints are caustic, and hazardous you will need to hold onto this and dispose of it properly at a hazardous recycling plant.
These things cannot be thrown away down the drain, or chucked into the ground, they need to be handled with care and consideration due to their hazardous properties.
Now, you may feel like you need to repeat the process again, this is not uncommon if your brush is suffering a bit from a heavy coating of polyurethane.
But, before you go soaking it again, place the same amount of mineral spirits into your second container and swirl the brush around again.
Chances are that you may see some promising results this time around simply from agitating the solvent, and you shouldn’t need to let it soak again.
But, if you are not seeing the results you want you can allow the brush to soak for a few hours again and repeat the whole process. Use your own judgement.
Once you have removed the most part of the polyurethane paint from the paint brush you can now soak your brush in some hot water. You should probably do this in a bucket or large container as mineral spirits and polyurethane are not meant to go down the drain.
You can also use some dish soap if you want to create a soapy water mixture as well if you feel like you need that extra kick. Furthermore, you could also use a brush comb now too to work through the bristles and work out any excess paint that may be stubborn. Remember to be gentle if you do this though.
7. Dry time
Now that you have removed all the remaining polyurethane from the brush, use some paper towels to pat your brush bristles dry. Make sure that you do not pull too hard on the bristles as this could loosen them and lead to a short brush lifespan.
Once you are ready store your brush for its next use. If it is a synthetic brush then wrapping it in some plastic will help protect it, if it is natural then old newspapers will do the trick. This will stop the bristles from bending or breaking during storage.
A few final considerations
Now that you know how to get rid of the hardened polyurethane that has been plaguing your brushes you can have more confidence in restoring your brushes.
We hope that implementing this tips and this process as soon as possible will help you to keep your brushes in great conditions for years to come.
If anything it will keep you from having to spend money on new brushes every time one hardens. Say goodbye to sad paintbrushes and keep your brushes at home happy and spick-and-span for years to come.