Newcomers often face the same issue when painting their 3D prints: The paint comes off rather easily. So in this article, I will tell you exactly how to paint your 3D prints correctly and avoid issues like peeling paint!
To paint 3D prints the surface of the prints has to be prepared first. The surface needs to be sanded and then a primer has to be applied to ensure that the paint will stick properly to the surface of the print. After that, the print can be painted with acrylic paint, enamel, or oil paint.
In this video, I explain my approach to painting 3D prints in easy-to-follow steps.
If you want to know more about painting plastics then consider reading my guide on how to paint plastic right here.
Painting 3D prints can be broken down into 6 easy steps:
- Remove supports and rough surface imperfections
- Smooth the surface of the model
- Clean the 3D print
- Apply a Primer
- Paint the model
- Apply a sealer (optional)
I will explain each of these steps individually in the following sections.
1. Remove Supports and Rough Surface Imperfections
This step is pretty straightforward. All you have to do is remove any supports from your 3D print.
This can usually be done with pliers but in some cases, the supports stick too well on the printed model.
In these instances, you can either use a heat gun to soften the filament at the contact points or, if you are dealing with a resin print, you can also submerge the print in some hot water to remove supports easier.
You might be left with some surface imperfections, especially where supports touched the model.
These can be removed with some sandpaper. I usually use 400-grid sandpaper to quickly fix these imperfections but any type of sandpaper or file is fine.
2. Smooth the Surface of the Model
Next, we have to smooth the surface of the print.
This step is somewhat optional depending on the quality of your print and if you want the layer lines to be visible or not.
I personally almost always smooth my 3D prints if I plan on painting them because the paint will often make the layer lines even more visible.
There are several ways to smoothen 3D prints and you can read all about the different approaches in my guide on how to smooth 3D prints properly right here.
Or you can watch this video.
In this guide, I will only cover one method which is smoothing the print with spray-on filler and filler out of the tube.
First I always fix big gaps or holes in the print with some filler out of the tube.
Simply apply the filler directly to the area that you want to fix and use some water and your fingers to smoothen the surface.
It doesn´t have to be perfect as we will sand the surface later on.
Let the filler dry for a few hours.
Then sand the filler until it is smooth and no gaps or holes are visible anymore.
Finally, apply a spray-on filler to the entire model. This is best done outside or in a well-ventilated area.
Let the filler dry and then sand the surface until it is smooth enough for your liking.
This will remove any layer lines.
3. Clean the 3D print
Next up, we have to quickly clean the surface before we apply the primer.
All we do in this step is remove any dust and debris on the surface of the print to prepare the model for priming and painting.
This can be done by using some soapy water to remove the durst.
4. Apply a Primer
This is quite an important step. You need a primer to ensure that the paint adheres properly to the surface of the model.
If you don´t apply a primer then you will have issues with paint peeling later on.
There are some paints that adhere directly to plastic without the need for a primer. But I don´t recommend them if you want to paint your model with a brush. Only use those if you want to completely recolor your model or areas of your model.
These primers ensure that you don´t lose any detail and they adhere really well to plastic.
Apply the primer in multiple thin layers and outside or in a well-ventilated area.
Let the primer dry and if you missed any areas then simply apply a second or third layer of primer until the whole model is covered evenly.
5. Paint the Model
Finally, the last step is painting the model.
You can use any paint you want but I highly recommend using acrylic paints.
Citadel is by far the most expensive acrylic paint you can get which is also why I don´t use these paints all too often.
I personally prefer Vallejo paints over most other alternatives as I found them to be really good and quite cheap in comparison to Citadel paints.
Simply apply the paint directly to your primed model. The paint should cover very well right away.
You can also use an airbrush if you want to apply the paint broadly or you can use contrast paints from Citadel or speed paints from Army Painter to lay down a nice base coat.
Contrast paints will dry darker in recesses which will automatically add some contrast to the model right away.
You can also mix and water down acrylic paints to create new colors or to glaze your models.
A wet palette can be useful if you plan on painting your 3D models more often with acrylic paints. You can read more about wet palettes right here.
6. Apply a Sealer (Optional)
This step is optional and I rarely seal my painted 3D prints.
But in some instances, you might want to consider sealing yours.
A sealer will protect your painted model from water, sun, and scratches.
So if your models are in danger of regularly getting wet then applying a sealer can help drastically increase their lifetime.
Simply apply the sealer directly to your print in multiple thin layers until the whole model is covered in a thin film of acrylic sealer.
What Kind of Paint Can Be Used for Painting 3D Prints?
There are some paints that can be applied to 3D prints directly without priming them first but I generally recommend priming the prints before painting them as it is just more reliable.
As a whole, 3D prints can be painted with any type of paint as long as the print has been sanded and primed beforehand. The easiest type of paint to work with is acrylic paint but primed plastic can also be painted with oil paints or enamel paints.
There are some paints that can be directly applied to 3D prints and I have a separate article where I go into detail about how and what kind of paints can be used for that.
You can read all about that in my article: How to paint plastic, right here.
But the easiest and safest way to paint 3D prints is by sanding and priming the print before applying the paint.
You can use any type of paint that you want but I highly recommend using acrylic paint. Especially acrylic paint from Vallejo is great for painting plastic.
You can also use different paints to paint your print. For example, you could paint the whole print with acrylic paint and then apply an oil wash over the whole thing to weather the paint job underneath.
How to Paint 3D Resin Prints
Resin 3D printers are getting more and more affordable and the quality of the prints is getting absolutely insane, as you can see in my Mars 2 Pro review right here. But are they any different to paint than regular 3D printed models?
As a whole, 3D resin prints can be painted with acrylic, oil, or enamel paints but the print has to be sanded slightly and a primer has to be applied to ensure that the paint will stick properly and permanently to the surface of the print.
It´s pretty much the same as painting regular 3D printed models with the sole exception that you don´t have to do as much sanding or clean up of the print in general because the print lines are so much finer compared to a regular 3D printer.
Do Resin Prints Need Primer?
Resin printers are fairly new for the crafts community so I get a lot of questions regarding priming the 3D resin print.
As a whole, a primer should be applied to the 3D resin print before painting it but there are paints that will adhere to the surface of the resin print directly. However, the easiest way to paint resin prints is by priming them first and then painting them with acrylic paints.
So they don´t need a primer but it is highly recommended to use one.
If you don´t apply a primer to the resin before painting it then you run the risk that the paint won´t adhere properly to the surface. This will in turn result in the paint peeling or chipping off.
Do 3D Prints Need Primer?
3D printing, in general, has been around for quite some time now but it is becoming more and more mainstream so I get asked a lot if you need to prime all 3D prints for painting.
3D prints don´t need a primer if they are not being painted. And even if they are being painted then using a primer is highly recommended but not necessary as there are paints that will adhere directly to plastic without a primer.
But, as I stated before, applying a primer before painting the print is highly recommended as it ensures that the paint won´t peel off later on.
Really the big takeaway here is that using a primer is always the best cause of action when painting 3D prints in general as it ensures that the paint always adheres properly to your 3D print and you will also need less paint because a primed surface will accept the paint much better.
Hi, I am a passionate maker and professional prop maker for the entertainment industry. I use my woodworking, programming, electronics, and illustration know-how to create interactive props and puzzles for Escape Games and marketing agencies. And I share my knowledge and my experience on this blog with you so that you can become a maker yourself.