Using a spray gun for painting can be a lot faster than using a brush or roller, while it is a bit messier, you can get better coverage in a shorter amount of time.
However, paints do not always tend to be ‘spray-gun’ ready, and you will have to thin your paint to be able to use this technique.
When using a spray gun you may worry if the paint will flow freely when you use it, the best way to do this is to thin it yourself, saving yourself the trouble of having to worry about buying different paint types, or damaging your spray gun.
There are many types of paint you could spray; latex, encapsulants, and of course, acrylic. The best way to learn to use spray guns is to learn to thin paints yourself, so you don’t have to switch paints or spray guns.
The way we will talk you through today, will work for any of these paint types, but most importantly acrylic, we will also tell you how to get your consistency right, so if you have paints of different consistencies, you will be able to thin it perfectly yourself.
Spraying Acrylic Paints: What You Need to Know
Thinning paint for a sprayer gun can be a tricky process. There are several solvents that can be used for thinning paint. Water, paint thinner and even mineral spirits can be options. But your choice will be dependent on both the type of paint used as well as the finish you are trying to achieve.
There are two very common paint categories for most applications: Oil based paints and Water based paints. The main difference when it comes to spraying is that Oil based paints cannot be thinned with water while water based paints can.
Acrylic and latex paints are water based paints while enamels are oil based (alkyd) paints. Spraying acrylic paints can be accomplished by thinning with water, paint thinner or even mineral spirits.
Paint pigmentation can also have an impact on spraying ability. Paint pigments are resins that are applied to a base to give color. The more resin in a paint, the harder it is to thin. Acrylic paints generally have a similar consistency and the thinning process should not change based on color.
Supplies you will need
Before you do anything, you need to have everything you need in advance, you don’t want to be halfway through mixing and realize you need to go back to the hardware store, so get everything beforehand, especially if you are doing a large project.
- Paint. You will obviously need paint for thinning. Without the paint there is no real project here.
- Water, or a paint thinner from the hardware store. Water is the most common agent used for thinning paint, it is often used with latex paints, but it can be used with any. However, you can also get a paint thinner from the hardware store. These are not hard to get and are good for first timers. We would recommend using this for acrylic, but there’s nothing to say you can’t give water a try either.
- Funnel. You will need a funnel to test the viscosity of the paint. It will give you a good visual of the consistency, so you can make sure it is right.
- Spray gun. If you are going to spray paint something, you need a spray paint gun.
- Cardboard, or another testing surface. It is always a good idea to have a test surface available so that you can test out your paint and make sure that it sprays well and adheres to your surface well too.
How to: A step-by-step guide
1. Mix your paint with 10% of its volume in water or thinner
This is the most cautious step, for every gallon of paint you have put in 12-13 ounces of water or thinner. This is about 10% of the volume of paint for each gallon you have.
It can also be useful to use a paint strainer to ensure that you are getting the right consistency for your sprayer tips. Use a stick to mix the paint and the thinner together.
2. Pour the mixture through the funnel/ strainer
The funnel is your visual test of if you can spray through your spray gun. Pour the mixture into the funnel slowly, and you should see it flowing freely out the bottom if it is the right consistency.
Do this over a bucket of over your paint/thinner mixture, so you do not waste any. If it does not flow freely through the funnel, then go to the next step. Do not forget you can use a strainer to check for clogs.
3. Increase/ decrease the ratio as you need to
You will have started with 10% of the volume of your paint. Increase this slowly, adding another 10% each time as you are mixing your paint if your mixture is too thick.
Do not jump drastically, if you do, you could miss out on that goal consistency where your paint is not too heavily diluted. Remember you want to preserve the color and adhesiveness too.
4. Test it out
If you feel like the paint is adequately thinned then test it out. Load the sprayer and apply to your sample surface. It should spray without getting stuck or slowing down and provide a clear and even spread.
5. Time to get painting
Finally, paint your wall, or whatever surface you are using. Your paint should also last longer as you have thinned it during the mixing period. This saves you money too!
Can you use alcohol to thin acrylic paint?
Yes. Alcohol can be used to thin acrylic paint. It is better to use alcohol when spraying acrylic paints when fast drying is important. Highly concentrated Alcohol evaporates very quickly under room temperature. Water does not evaporate as fast.