3D printing can be an amazing tool for a lot of creative crafts but 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!
As a whole, 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, enamel, or oil paints.
You can see how I usually paint my 3D sculptures in this video right here.
3D prints are basically plastic, so if you want to know more about painting plastics then consider reading my guide on how to paint plastic right here.
I recently got my hands on the Mars 2 Pro resin 3D printer from Elegoo and I instantly started creating a small sculpture to see how 3D printing can be used in the arts and crafts world.
In this article, I will share how I painted the model and what I did to prepare the model for the painting, so that you know exactly how to paint your 3D prints and ensure that they will turn out great.
How to Sand 3D Prints Properly
The first thing you need to do is prepare the surface of the 3D print for painting. So we will smooth the surface, if necessary, with some sandpaper.
To sand the 3D print it is important to get rid of any access like printing supports or threading from the print by removing those with a craft knife, or pliers. Then remove any rough parts of the print with some 100 to 120-grit sandpaper and move your way up to 300 grit to smooth the surface of the print.
This process needs to be done with regular 3D printed models as well as resin prints. But you will have much less smoothing to do with resin prints.
A pro tip when working with non-resin prints that have a lot of visible print lines is using spray-on spatular.
Simply apply a few thin layers of spray-on filler to your 3D print and then start the sanding process. The filler is easier to sand than the plastic of the print itself and it will fill in the small uneven surface details like print lines.
This way you don´t have to sand as much.
You can find spray-on filler right here on Amazon or in your local hardware store in the section for car appliances.
What Kind of Paint Can be Used for Painting 3D Prints?
There are some paints that can be applied to 3D prints directly without printing them first but I generally recommend printing 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 the prints 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 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 Prints With Acrylic Paint
If you are a beginner then I highly recommend using acrylic paint for painting your first few prints. They are easy to use and you can get them quite cheaply.
To paint 3D prints with acrylic paint the prints first have to be prepared for painting by sanding them and applying a primer to the surface. Then the acrylic paint can be applied directly to the print. After the paint has dried a thin coat of matt acrylic sealer can be applied to protect the paint.
This sculpture that I made was almost entirely 3D printed with the Mars 2 Pro and I painted it with acrylic paints.
It is possible that you need multiple layers of acrylic paint to sufficiently cover the surface. I usually need two or three layers.
After the acrylic paint has dried you can apply a thin coat of matt acrylic sealer to the whole print to seal the paint. This will add another layer of protection to your paint job.
You can get an acrylic sealer at your local hardware store or right here on Amazon.
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 make sure 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.