How to Assemble and Finish Your 3D Printed Miniatures Like a Pro

So, you've picked up some awesome 3D printed miniatures, but before they’re ready for the tabletop or display shelf, they need a little extra care. While 3D-printed minis come with incredible detail, they often have small imperfections, like leftover supports, that need smoothing out. Plus, some miniatures, due to their final size, come in multiple parts that require careful gluing. The good news? With the right techniques for sanding, gluing, and prepping, you can make your minis look smooth, seamless, and ready for paint.

In this guide, we’ll walk you through the best practices for assembling and finishing your 3D-printed miniatures like a pro. You’ll learn how to clean up surfaces, securely attach parts, and prep your minis for that perfect final coat. Whether you’re new to the hobby or an experienced painter, these simple steps will help you get the most out of your models and bring them to life. Let’s get started!

Tools You’ll Need

Before you start assembling and finishing your miniatures, you'll need the right tools for the job. Here’s a list of must-have supplies and why they’re essential for achieving a smooth, professional look.

Sanding and Smoothing Tools

• Sandpaper (400–1000 Grit) – Used to smooth out layer lines and surface imperfections. Start with a lower grit (400) for rough areas, then move up to 1000 for a polished finish.
• Needle Files – Great for getting into small details, like between armor plates or folds in clothing, where sandpaper might be too bulky.

• Sanding Sticks or Sponges – These flexible tools conform to curved surfaces, making it easier to smooth out rounded edges and organic shapes.

Gluing and Assembly Tools

• Super Glue (Cyanoacrylate) – The go-to adhesive for bonding 3D printed parts. It dries quickly and forms a strong bond, making it ideal for assembling multi-part miniatures.

• Plastic or Resin-Specific Glue – Some miniatures may work better with specialty glues designed for resin or PLA prints, ensuring a more secure bond.

 

• Clamps or Rubber Bands – Helpful for holding glued parts together while they set, preventing misalignment or gaps.

 

• Tweezers – Perfect for handling small parts with precision, especially when attaching tiny details.

Prepping and Cleaning Tools

• Hobby Knife or Precision Cutter – Used to remove support remnants, trim flash, or refine details before sanding.
• Soft Brush – For giving your 3-D printed miniatures a final wash.
• Lint-free Cloth – To safely dry your miniature before applying any glue or primer.
• Primer Spray or Brush-On Primer – A crucial step before painting, primer helps the paint adhere better and reveals any imperfections that may still need smoothing.

Having these tools on hand will make the finishing process smoother and help you achieve the best results for your miniatures. Up next, we’ll go over exactly how to use them to get your models looking their best!

Sanding and Smoothing Your 3D-Printed Miniatures

Before a resin-printed miniature is ready for paint, it needs to be properly smoothed. Typically, this process starts with removing supports, washing away excess resin, and curing the model under UV light. The good news? Our miniatures come with these steps already taken care of! However, you may still find small support remnants or faint layer lines that need a little extra attention to achieve a flawless finish.

Start by inspecting your miniature under good lighting to spot any rough areas.

Use a hobby knife, Precision Cutter, or needle file to gently trim or smooth any small support nubs that may remain.

For visible layer lines, begin sanding with 400-grit sandpaper or a sanding stick, working in circular motions to avoid flat spots. If the surface needs further refinement, step up to 800-1000 grit sandpaper for a smoother finish.

For hard-to-reach areas, a needle file or sanding sponge can help maintain details without losing sharp edges.

Once finished, give your model a quick rinse or wipe with isopropyl alcohol to remove any dust before priming.

Once you're done sanding, it’s a good idea to wash your miniature with mild soap and warm water to remove any dust or fine resin particles. Use a soft brush or toothbrush to get into small crevices without damaging delicate details.

Rinse thoroughly, then pat dry with a lint-free cloth or let it air dry completely before moving on to priming. This final step ensures a clean surface, helping your primer and paint adhere smoothly for the best possible finish.

Gluing and Assembling Your 3-D Printed Miniatures

Some 3D-printed miniatures come in multiple parts, whether due to their size, complex design, or pose. Proper gluing is essential to ensure a strong, seamless bond that holds up over time. For most miniatures, super glue (cyanoacrylate) is the best choice. It dries quickly and forms a durable connection. 

Before applying glue, make sure the pieces fit together properly by doing a dry test fit. If any edges don’t align perfectly, a light sanding with a needle file can help create a better contact surface. Just as important as a good fit is a clean surface. Any dust from sanding can weaken the bond. 

Before gluing, take a moment to wipe the contact points with a dry, lint-free cloth or a bit of isopropyl alcohol to remove any debris. This ensures the glue adheres directly to the material, rather than a layer of dust that could cause weak spots.

For larger or more fragile parts, you may want to reinforce the bond. One way to do this is by pinning, which involves drilling a small hole in both connecting pieces and inserting a thin metal pin (such as a cut paperclip or brass rod) before gluing. This adds extra strength, especially for parts like arms, weapons, or bases.

If you notice any small gaps after gluing, you can fill them with a tiny amount of liquid green stuff or modeling putty, then sand it smooth once dry. With careful gluing, a clean surface, and reinforcement when needed, your miniatures will be solid, sturdy, and ready for the next step—priming and painting!

Priming Your 3D Printed Miniatures

Priming is one of the most important steps in finishing your 3D-printed miniatures. Without primer, the paint may not adhere properly, leading to chipping, uneven coverage, or a blotchy finish.

A good primer creates a smooth, even surface that helps paint stick while also revealing any small imperfections that might need additional sanding. This is especially crucial for resin miniatures, as their naturally smooth surface can repel paint if left unprimed. 

The best primers for resin are spray primers designed for miniatures, such as Vallejo Surface Primer, Army Painter Primer, or Citadel Primer. These offer great adhesion and a thin, even coat that won’t obscure fine details.

If you prefer brush-on primer, Stynylrez or Vallejo’s brush-on primers are excellent choices, especially for touch-ups or areas where spray primer is difficult to apply.

To prime your miniature properly, follow these steps:

1. Ensure the model is clean – Wipe off any remaining dust or oils with a soft brush or a quick wash with mild soap and water. Let it dry completely.

2. Choose a well-ventilated area – If using spray primer, work outdoors or in a ventilated space, and shake the can well for at least a minute.

3. Apply thin, even coats – Hold the can about 6-12 inches away and spray in short bursts, rotating the miniature to cover all angles. Avoid spraying too much at once, as thick layers can obscure details.

4. Let it dry fully – Most primers dry to the touch in 10-15 minutes, but it's best to wait at least an hour before handling to ensure a strong bond.

5. Inspect and touch up if needed – If you missed any spots, use a brush-on primer to fill in gaps without overspraying.

Once primed, your miniature will have a smooth, paint-ready surface that enhances color vibrancy and durability. With a properly primed model, your paints will apply more evenly, and your finished piece will be more resistant to wear and tear!

Final Thoughts

With the right techniques and a little patience, assembling and finishing your 3D-printed miniatures can be just as rewarding as painting them. By carefully sanding away imperfections, securely gluing parts, and properly priming your models, you set the foundation for a professional-quality finish. 

Whether you're a seasoned hobbyist or just starting, taking the time to prep your miniatures properly will make all the difference in bringing your creations to life. Now that your models are prepped and primed, it’s time for the fun part—painting!