How to Paint 3D Printed Models: A Complete Beginner-to-Finish Guide

3D printed models are excellent canvases for custom paint jobs. Whether you are painting a fantasy display piece, gaming accessory, creature, terrain piece, or decorative model, a few simple preparation and painting techniques can make an enormous difference in the final result.

Many monochrome models from Nexus PC Works and Games are printed in light gray PLA intentionally. Light gray makes sculpted detail easy to see and provides a neutral starting point for customers who want to paint and customize their model.

What You Will Need

• Mild dish soap and water
• Soft brush or toothbrush
• Fine-grit sandpaper or sanding sticks
• Optional filler or modeling putty
• Primer suitable for plastic
• Acrylic paints
• Medium and small detail brushes
• Optional washes, inks, or contrast-style paints
• Optional airbrush
• Clear matte, satin, or gloss sealer

1. Inspect and Clean the Print

Inspect the model for loose strings, small support remnants, rough spots, or other imperfections. Remove them carefully with appropriate hobby tools. Wash the model with mild dish soap and lukewarm water, rinse thoroughly, and allow it to dry completely. This removes dust and skin oils that can interfere with primer and paint adhesion.

2. Prepare the Surface

FDM printing naturally creates layer lines. Many detailed models can simply be primed and painted, but for a smoother display finish you can lightly sand the most visible surfaces. Use light pressure because PLA can soften if excessive friction creates heat.

Filling Layer Lines and Seams

For larger gaps, seams, or particularly visible layer lines, use a model filler or putty compatible with plastic. Let it cure fully and sand it smooth. You do not need to eliminate every layer line to create an attractive painted model.

3. Prime the Model

Primer gives acrylic paint a reliable surface to grip and can reveal areas that need additional cleanup. Use a primer intended for plastics or miniatures and follow the manufacturer’s application and safety instructions. Apply several light coats instead of one heavy coat so fine details remain visible.

Choosing a Primer Color

• Gray: versatile and excellent for most projects.
• Black: useful for dark, metallic, grim, or heavily shadowed schemes.
• White: useful for bright colors, pastels, and vivid fantasy schemes.

Light-gray PLA helps you see the sculpted details, but primer is still recommended before a serious paint job.

4. Choose Your Paint

Water-based acrylic model and miniature paints are a dependable choice for PLA. Craft acrylics can also work well on larger pieces, although thicker paints may need thinning. Several thin coats usually preserve detail and produce a smoother result than one heavy coat.

5. Apply the Base Colors

Begin with the largest color areas and establish the main color scheme. Allow each coat to dry before deciding whether another coat is needed. Painting deeply recessed areas early can make later cleanup easier.

6. Add Shadows With a Wash

A wash is thin paint designed to flow into recessed areas. It quickly emphasizes cracks, scales, stone texture, armor panels, fur, folds, teeth, wood grain, and other sculpted detail. Prevent large pools from drying on flat surfaces.

7. Highlight With Dry Brushing

Dry brushing works especially well on textured 3D prints. Put a small amount of lighter paint on a brush, wipe most of it away, and lightly drag the brush across raised surfaces. The remaining paint catches edges and high points, creating quick highlights.

8. Paint Fine Details

Once the base colors, shadows, and highlights are established, paint smaller details such as eyes, teeth, runes, buckles, gems, trim, weapons, or control panels. A small brush helps, but good brush control is more important than using the tiniest brush available.

9. Optional Airbrushing

An airbrush is useful for smooth gradients, large surfaces, glowing effects, atmospheric shading, and fast base coating, but it is not required. Traditional brushes can produce excellent results.

10. Correct Mistakes as You Go

Most acrylic painting mistakes are easy to fix. Let the area dry, repaint it with the underlying color, and try again. A small mistake rarely requires stripping an entire model.

11. Seal the Finished Model

After the paint has dried completely, a clear protective sealer can help protect the finish from handling and wear.

• Matte: reduces shine and works well for figures and terrain.
• Satin: provides a slight sheen suitable for many display pieces.
• Gloss: creates a shiny finish useful for wet surfaces, gems, polished armor, eyes, and special effects.

A Simple Beginner Painting Recipe

1. Clean the print and remove obvious rough spots.
2. Apply light coats of primer.
3. Paint the major areas with acrylic base colors.
4. Apply a darker wash into recesses.
5. Dry brush raised surfaces with a lighter color.
6. Paint small details.
7. Let the model dry completely.
8. Apply a clear protective sealer.

Common Problems

Paint Is Not Sticking

Make sure the print is clean, dry, and properly primed. Dust and oils can interfere with adhesion.

Details Are Disappearing

Your primer or paint may be too heavy. Use thinner coats and allow them to dry between applications.

Layer Lines Are Too Visible

Lightly sand visible areas and use filler where necessary before priming again. Texture-heavy designs often hide layer lines naturally after washes and dry brushing.

The Model Looks Flat

Add contrast. A darker wash creates shadows while dry brushing or edge highlights bring raised areas forward.

Why We Use Light Gray for Many Monochrome Prints

Light gray is a practical color for an unfinished model. It shows sculpted detail better than very dark filament, avoids the harsh brightness of white, and provides a clean neutral surface for inspection and customization. Filament color does not replace primer, but light gray makes an excellent starting point.

Make It Yours

There is no single correct way to paint a 3D printed model. You can create a highly detailed display finish, use quick tabletop techniques, or choose a simple color scheme. Start with techniques that fit your project and add complexity as your skills grow.

Looking for a model to customize? Visit the Nexus PC Works and Games 3D Printed Products collection to see available models and accessories.