We can consider painting the 3D printed model to be an essential part of the 3D printing process in most cases, especially considering that a large portion of 3D printed models is printed for aesthetic purposes, such as figurines, which require painting to create a successful final product.
On the other hand, just like the 3D printing process itself, painting a 3D printed model also comes with its own set of nuances and challenges, ranging from paint selection to correctly preparing the model for the paint to stick without issues.
In today’s article, we will be diving into the paint selection process of painting a 3D model, particularly by examining how acrylic paint reacts with PLA, which are some of the most widely-used components in painting and 3D printing, respectively.
So, can you use acrylic paint on 3D models printed with PLA without issues?
Acrylic paint is a perfect choice for painting the 3D models you have printed with PLA filament, whether you are a beginner or an expert, as it’s straightforward to apply, quick-drying, and water-soluble, making it highly unlikely to experience any issues during the painting process.
Moving forward, we will take a deeper look into whether it’s possible to use acrylic paint on PLA 3D prints, find the optimal way to conduct the painting process, discuss whether acrylic paint is the best option for painting PLA, and finally, quickly troubleshoot the issue of acrylic paint not sticking to 3D models printed with PLA.
Can You Use Acrylic Paint on PLA 3D Prints?
There is no denying that PLA is one of the most popular filament types in 3D printing and that acrylic paint is one of the most common paint types in art, and as both materials owe a significant portion of their popularity due to their ease of use, the question of whether the two would work well together immediately comes to mind.
You can indeed use acrylic paint on your PLA 3D prints with ease, even if you will be painting a 3D printed model for the first time, as acrylic is one of the more forgiving paints that highly reduce the chance of any errors occurring during the painting process.
As it’s possible to find acrylic paint in both glossy and matte forms and practically any color of your choice, it provides a great deal of flexibility in how your 3D printed model will look, allowing you to shape the coloring of your model as you desire.
How to Paint PLA 3D Prints with Acrylic Paint?
Taking the correct approach for painting your PLA 3D printed models with acrylic paint is vital to ensure success since, just as the 3D printing process itself requires following a particular methodology, the process of painting the model is also not something that we can do blindly.
While it’s possible to apply acrylic paint to your PLA 3D printed models directly with a paintbrush and achieve a decent amount of success, we highly recommend going through the steps of sanding and priming before applying the paint for best results.
The first step we recommend in preparing a PLA 3D printed model for the painting is to clean it thoroughly to ensure that no dirt or grease can prevent the paint from sticking correctly. You can either wipe the model with soap and water or isopropyl alcohol for this process.
The next step is sanding the model to eliminate all roughness on the surface and create a smooth area for the painting process, which will make the paint look much better. For the sanding process, we recommend dry sanding with 120-grit and 200-grit, respectively, and finishing up with wet sanding with 400-grit sandpaper.
After the sanding process is over, you will need to apply two coats of primer, such as acrylic gesso, on the surface of your 3D printed model. The primer will fill all the cracks and imperfections on the surface of your model, creating an entirely smooth surface that is ready to paint.
When the primer is fully dry, you can start painting your 3D printed model with acrylic paint. We highly recommend waiting for the paint to dry after each coat and applying at least four to five coats for the best results.
As painting a model with rough edges will make them even more apparent to the eye, following these steps, instead of directly and constantly applying paint, will ensure that your 3D printed model is smooth and that the coloring is well-defined.
Is Acrylic Paint the Best Option for Painting PLA 3D Prints?
Being aware of the alternatives and the advantages and disadvantages they bring to the table is always a significant part of achieving success, as the fact that something works well doesn’t always mean that there aren’t better options available.
While it wouldn’t be correct to say that any particular paint is the best option for painting PLA 3D prints, as paint selection largely depends on factors such as your experience and your expectancy from the paint, we can consider acrylic paint to be one the best choice for beginners.
Here are the reasons behind our recommendation for acrylic paint usage if you are a beginner:
- Quick-drying – The acrylic paint drying quickly reduces the chance of any errors occurring during painting, as you won’t be able to smear the previously painted areas accidentally.
- Easy and flexible application – As all you need is a simple paintbrush to apply acrylic paint to your 3D printed model, you can utilize many different brush sizes to make the painting process more precise and efficient.
- Water-soluble – Acrylic paint being water-soluble, allows you to wash it off before it dries, which will help you to correct any mistakes that could have taken place during the painting process.
In the particular case of single-color painting, where there is not much that can go wrong with the details, spray paint is another excellent alternative for printing your PLA 3D prints, which makes the painting process considerably faster and less demanding in terms of effort.
Acrylic Paint Not Sticking to PLA 3D Print – What to Do?
While acrylic paint and PLA work well in general, considering that you have followed the correct approach for conducting the painting process, there are also scenarios where the painting process can fail due to the acrylic paint not correctly sticking to the PLA 3D print.
While acrylic paint should stick to 3D printed models that you have printed with PLA without issues in most cases, in the rare instances where you’re having a problem with the paint sticking, it’s primarily due to skipping the pre-painting process of cleaning, sanding, and priming.
If this is the case for you, we highly recommend starting with cleaning the printed PLA 3D printed model with soap and water, drying it thoroughly, sanding it, applying primer, and finally, waiting for the primer to dry before moving on to the painting process with acrylic paint.
There is no surprise that the combination of acrylic paint and PLA immediately comes to mind for painting a 3D printed model, with both materials being extremely straightforward to use in their respective fields of art and 3D printing.
To quickly recap, acrylic paint is definitely a great option for painting the 3D models you have printed with PLA filament regardless of your experience level with post-processing, especially considering the many benefits it brings for ease of use, such as easy application and water solubility.
While there are many other paint options you can also use to paint PLA 3D printed models successfully, we highly recommend going with acrylic paint due to the ease of use it brings to the table, especially if you are starting with painting 3D printed models for the first time.