Definitive Guide to Miniature Priming 🎨 (Spray, Airbrush, and Brush)

Hey there, maker! I'm Mr. Resin, and before you dive straight into painting that freshly printed miniature, hold on a second. We need to talk about that step that many people skip and that, trust me from experience, changes EVERYTHING: miniature priming. I know, I know... the urge to start painting can be a beast that's hard to tame, but believe me, jumping in headfirst is a first-class ticket to frustration.

Why is priming the step that defines your miniatures?

Don't worry, I've got you covered! You're probably thinking: "Is it really that big a deal? I just want to paint!" I've been in your shoes, I get it completely. But after years and a few ruined minis, I've learned my lesson: a good primer is what separates a professional finish that survives battles and house moves from paint that chips off at the slightest touch. It's a fundamental step, no matter whether you're using one of the best photopolymer resins or if you're more of an FDM filament person.

The bridge between the piece and the paint

Think of primer as the invisible glue that bonds your miniature and the paint together. In my experience, the surfaces of printed pieces, whether resin or plastic like PLA, are super smooth and non-porous. Acrylic paint, on its own, slides right off them because there's nothing for it to grip onto.

Primer creates a base coat with an ultra-fine microtexture, giving the paint that "bite" it needs to adhere with incredible strength. It's like trying to write with a pen on glass versus writing on paper. You need that slight roughness to make everything work.

From experience I can tell you that primed minis not only hold up much better to handling during games, but they also resist changes in temperature and humidity without the paint cracking or peeling. It's the life insurance policy for all those hours of work!

A unified canvas for vibrant colours

Another superpower of miniature primer is that it unifies the colour of the entire piece. Imagine you've printed a figure using a dark grey resin. If you try to paint yellow directly on top, you'll need a million coats to stop the base colour from "killing" the brightness, leaving you with a dull, lifeless yellow.

By applying a coat of primer, you create a canvas in a neutral, uniform colour. This gives you some serious advantages:

• Colours that pop: A white or light grey base will make your colours vibrant, especially warm tones like yellows, reds, and oranges.
• You save paint (and time): You won't need to apply coat after coat to get good coverage. Fewer passes, fewer pots of paint used up.
• Army consistency: If you're painting a large number of figures, you ensure they all start from the same base. The final result will be far more cohesive.

The tell-tale that saves you from disaster

And here's a trick I've come to appreciate over time: primer is the ultimate tell-tale. It's the best quality control tool you'll have before you start painting.

That thin, matte coat brings all the little gremlins to light that you simply can't see with the naked eye. Suddenly, those stubborn layer lines, the support marks you could have sworn you sanded away, or a small gap appear with startling clarity. This gives you one last golden opportunity to grab the filler or give it another pass with the sandpaper before it's too late.

Trust me, it's infinitely easier to fix it at this point than when you already have three layers of paint on. Investing this little bit of time at the beginning is the key to making your hard painting work shine the way it deserves. Let's get to it! 😉

How to prepare your miniature before priming

OK, we're clear that miniature priming is a sacred step. Now it's time to roll up your sleeves and get the piece in perfect shape, because not even the best primer in the universe will work miracles if the surface is a mess. Trust me, good preparation is 50% of the battle won.

I'm going to share my ritual, the one I follow religiously before a single drop of primer gets anywhere near my figures. This guarantees you a perfect canvas.

Remove the supports, but without leaving a trace

The first enemy to tackle is the supports. Whether in resin or FDM, removing them properly is an art that requires patience. Don't even think about yanking them off!

• For resin: My go-to trick is to submerge the freshly printed piece (before the final curing, mind you) in hot water for about 30-60 seconds. This softens them nicely. Then, with fine cutting pliers, they come off almost on their own and leave minimal marks.
• For FDM: Here things get a bit more stubborn. I use fine-nose pliers and a modelling blade to get into all the nooks and crannies. The trick is to cut leaving a tiny margin that I then sand down, rather than cutting too close and risking taking a chunk out of the mini.

The art of sanding and polishing

Once the mini is free of supports, it's time to hunt down imperfections: small marks, bumps, or the notorious FDM layer lines.

My arsenal for this is simple but effective: a set of modelling files and fine-grit wet-and-dry sandpaper (between 400 and 1000 is a good starting point). I always sand gently, using circular motions to avoid leaving ugly grooves. Wet-and-dry sandpaper, especially on resin, is wonderful for achieving super smooth finishes.

A golden tip: after sanding, take an old dry brush and sweep it all over the miniature. The fine dust that's generated is the number one enemy of a smooth, even primer coat.

Thorough washing is non-negotiable

This is the step most people skip, and the one that causes 90% of the drama with paint that won't stick. The piece has to be spotlessly clean! You need to remove any uncured resin residue, sanding dust, or the grease from our own fingers.

My foolproof method is a good soak in isopropyl alcohol (IPA). I submerge the figure for a few minutes and scrub it with an old toothbrush (one you use only for this purpose, please!). IPA dissolves any residue and leaves the surface ready for action. If you want to know more about this magic liquid, check out my complete guide on the use of isopropyl alcohol.

If you use water-washable resin, the process is the same but with water and a little soap. Just make sure to rinse thoroughly with clean water afterwards to leave no trace of soap.

The final curing that seals everything

When the resin miniature is clean and completely dry (and when I say completely, I mean COMPLETELY dry), it needs its final UV light session. This finishes hardening the piece and leaves it stable for the battle ahead.

Don't go overboard with the curing time or the resin can become brittle. For a standard-sized mini, I usually give it between 3 and 5 minutes on each side in my curing station. If you leave it in the sun, the time will depend on how strong the sun is that day.

With these steps, your miniature is ready for glory. Now then, on to that primer!

Choose the perfect primer for each project

Right, let's talk primer. That magical coat that changes everything. Getting into the world of miniature primer is like opening a new toolbox: there are sprays, bottles for airbrush, for brush, colors ranging from black to white and everything in between… It's a little overwhelming at first! But don't worry, that's what I'm here for — to help you make sense of it all so you know exactly what you need.

Application methods: spray, airbrush, or brush

Your first big decision. And no, there's no single correct answer. In my experience, the best option is the one that suits you, your space, and of course, the mini in front of you.

• Spray Primer: This is the workhorse, the all-rounder. It's fast, leaves a super even coat, and is perfect when you need to prime an entire army or large pieces. The downside? You need a well-ventilated space, like a balcony or terrace. And watch out on very humid or cold days, as it can leave a grainy texture that's a real pain.

• Airbrush Primer: For me, this is the top-tier option. The control it gives you is simply unbeatable. It lets you lay down ultra-thin coats that preserve every last micropore in the resin. Ideal for competition pieces or characters with details you don't want to lose at any cost. The initial investment in the equipment (airbrush and compressor) stings a bit more, but the results speak for themselves.

• Brush Primer: The ultimate lifesaver. Perfect if you paint in a flat with no balcony, for those last-minute touch-ups, or if you're only prepping one mini and don't feel like setting up the whole spray operation. The key trick is to thin it down a little with water so you don't get brushstroke marks. It's, by far, the cheapest and most accessible option.

My in-the-trenches advice: If you're just starting out, a good spray is your best friend. It'll give you excellent results without any fuss. Once you get the hang of it and want that extra level of finesse, make the jump to airbrush. And the brush… always keep a bottle on hand. It'll get you out of more than one tight spot.

The psychology of color: black, white, grey, and more

The color of your primer isn't just an aesthetic choice — it's pure strategy! Choosing wisely can save you hours of work.

• Black Primer: My favorite for dark and dramatic color schemes. The advantage is huge: any nook and cranny your brush doesn't reach stays black, creating instant natural shadows. It works brilliantly for armor, monsters, or grim settings. That said, be prepared to apply more coats if you want your yellows or reds to really pop.

• White Primer: The perfect base for colors you want to really "explode." Yellows, oranges, fuchsias, lime greens… they all gain spectacular intensity over white. The downside? It's unforgiving. Every unpainted gap will stick out like a sore thumb and will force you to be more careful with your shading.

• Grey Primer: The ultimate all-rounder. A neutral grey is the perfect middle ground. It doesn't dull bright colors like black does, but it helps define shadows better than white. If you're not sure which way to go or your mini has a varied color palette, grey is your safe bet. It works well with everything.

• Colored Primers: These are a fantastic shortcut! There are more and more options available: reds, blues, greens, bone color… They let you apply the primer and base coat in one fell swoop. If you're painting an Ultramarines army, for example, a blue primer gets 70% of the work done for you. Magic!

If you want to explore and see all the available options, I invite you to head over to the miniature primers section of our store. I'm sure you'll find the one for you!

To make it even easier, I've put together this table so you can decide at a glance what suits you best.

Comparison Table of Primer Types for Miniatures

Use this table to quickly decide which priming method best suits you, your setup, and the result you want to achieve.

I hope this guide has given you a much clearer idea of where to begin. Remember that, at the end of the day, the most important thing is to experiment and find what works best for you. Let's get priming!

Master application techniques like a professional

You already have the miniature and the primer in hand. The moment of truth has arrived! Applying it well is quite an art, but don't worry, that's what I'm here for. I'm going to share all my secrets with you.

No matter which tool you choose, the goal is always the same: achieving a thin, even coat that respects every last detail of your miniature. Let's get our hands dirty!

The drip-free spray trick

Spray primer is great for how quick it is, but it also has a temper and can catch you off guard if you're not careful. The secret isn't in force, but in control.

First, shake the can like your life depends on it. And I'm not joking — give it at least a solid two minutes so all the components mix perfectly. Trust me, this step makes all the difference.

Then, distance is key. Position yourself about 20-30 centimetres from the miniature. If you get too close, you'll drown the details in a blob of paint. And if you go too far, the paint will dry in the air and leave you with a horrible sandy texture that will ruin all your work.

Here comes the master move: don't just aim and fire. Start spraying outside the miniature, make a quick, controlled pass covering it from side to side, and finish spraying outside again. It's a steady sweep, like you're a priming ninja.

My golden tip: It's a thousand times better to apply two or three very thin coats than a single thick one that ruins everything. Apply one pass, wait about 10-15 minutes for it to dry to the touch, then go again. Patience here is your greatest ally for a perfect miniature priming.

The precision of the airbrush

If you're looking for maximum control and a competition-level finish, the airbrush is your best friend. Here the game changes — we're talking about thinning and pressure. Every primer brand is its own world, so there's no magic formula, but let me share my starting point.

Typically, I aim for a consistency similar to skimmed milk. I start with a ratio of 2 parts primer to 1 part thinner specifically for airbrush use and adjust from there. A good trick to tell if it's just right is to watch how it runs down the side of the cup.

As for pressure, when priming I work between 18 and 25 PSI. This gives me enough force for a steady flow, but without being so aggressive that it creates "spiders" or floods the details. If this world sparks your curiosity, I recommend checking out my guide on how to get started with an airbrush for miniatures, where I break it all down.

The passes, just like with spray, should be smooth and controlled, building up coverage little by little.

The brave brush user

Priming with a brush is a challenge, I won't lie to you, but sometimes there's no other option. For a good result that doesn't leave a map of brushstrokes, the secret lies in the technique.

• Dilution, please: Never use primer straight from the pot! Put a drop on your wet palette and add one or two tiny drops of water. The idea is to make it flow, but without the pigment separating.
• Very thin layers: Apply a first coat stretched out very, very thinly. Don't worry if it doesn't cover completely — that's normal! Its purpose is to create a first adhesion layer for whatever comes next.
• Stippling: For complex areas full of nooks and crannies, instead of dragging the brush, dab lightly with the tip. This technique is great for getting the primer into every spot without it building up.

It's a slower process, yes, but with patience you can achieve a more than decent finish. Perfect for touch-ups or for those days when you can't use the spray or airbrush.

The Pro trick: zenithal priming

Once you feel comfortable with the basics, you have to try this. Zenithal priming (zenithal priming) is a technique that pre-shades your miniature and makes your life so much easier. It's a game changer, I guarantee it!

1. Black Base: First, give the entire miniature a coat of black. Don't hold back. Make sure you cover it from every angle so there isn't a single gap.
2. Grey Light: Now, take a grey primer and apply it only from above, at an angle of about 45 degrees. Imagine it's the late afternoon sun lighting up the figure.
3. White Touch: Finally, with white primer, give it a very light and quick pass from directly above (a 90-degree angle). Think of the strong midday sun.

The result is a figure that already has its main lights and shadows defined before you even touch a colour. The colours you apply on top will look far more natural and with more volume from the very first minute. Your minis are going to level up, guaranteed!

How to fix the most common priming problems

It's happened to all of us. You finish priming, you feel like the king of the world, you lean in to admire your work and... your heart stops. Disaster! Even the most experienced painter has had a primer go wrong on them at least once. Me included, for the record.

The good news is that most of these disasters have a solution. Here I'll walk you through the most typical mistakes you might run into when using miniature primer and how to get out of trouble without having to throw the figure out the window.

The dreaded "sandpaper texture" or grainy primer

This is, without a doubt, the number one problem, especially if you use spray. You apply the coat to your mini and, as it dries, it has a rough feel, as if you had sprinkled sand over it. The surface, which should be smooth, now looks like sandpaper.

This usually happens for a couple of very specific reasons:

• You were spraying from too far away: If you move too far back (more than about 30 cm), the primer droplets dry in the air before reaching the figure. What lands is a dry powder that creates that horrible texture.
• The weather isn't cooperating: A very humid day or sweltering heat can wreak havoc on spray application. The result is the same: a grainy, poorly adhering coat.

How do I fix it? If the damage is minor, there's hope! Let it dry completely and then sand the area with extreme care. Use an extra-fine grit sandpaper, like 1200 or higher. If the damage is total, the best thing is to be patient, strip the paint, and start from scratch.

Oh no, I've covered all the details!

A classic beginner mistake (and one made by those of us who paint in a rush, let's be honest). You get carried away with the spray or airbrush and suddenly your character's face is a featureless mass with no eyes or mouth, and that cool armour is now a smooth blob. Panic!

If you notice it right away, act fast. While the primer is still wet, grab an old dry brush and use it to remove the excess paint from the recesses.

My personal trick in these cases, especially with resin, is a cotton swab dampened with a little isopropyl alcohol. I pass it with extreme gentleness over the "flooded" areas to lift the excess paint. Watch out! Do it very carefully or you'll take the entire primer coat with it.

The paint cracks or peels

This is the most frustrating problem of all. You finish painting, the miniature looks exhibition-worthy, you apply the final varnish coat and... the next day, the paint has cracked or peels off at the slightest touch.

The cause is almost always poor preparation of the figure.

• Lack of cleaning: This is reason number 1. If the miniature had traces of finger grease, dust, or especially release agents from the manufacturing process, the primer didn't bond properly. The paint is adhering to the primer, but the primer isn't adhering to the mini.
• Very thick primer coats: Applying too thick a primer coat can cause it to contract and crack as it dries, taking all the paint on top of it with it.
• Product incompatibility: This is less common with quality hobby brands like Vallejo, but it can sometimes happen that a lacquer primer reacts badly with an acrylic paint, for example.

What do I do now? Here, unfortunately, there are no shortcuts. The only reliable solution is to strip the miniature completely and start over. This time, make sure to give the piece a good scrub before anything else. A bath in isopropyl alcohol and a gentle brush is the best life insurance for your paint work.

Frequently asked questions about miniature priming

Right, let's get into it. After hundreds of primed minis, I've seen the same questions come up again and again in forums and groups. So I've put together this little Q&A to answer them once and for all. Let's go!

Is priming a resin miniature really mandatory?

The short and direct answer is: yes, always. Think of it this way: resin (and FDM filament too) is super smooth, almost like a mirror at a microscopic level. Acrylic paint needs something to grip onto, a surface with a little "tooth".

Without primer, paint simply sits on top. At the first scratch, temperature change, or just over time, it will chip and all your hard work goes down the drain. Skipping this step is asking for trouble, I'm telling you from experience. Don't risk it!

Can I use the same primer for resin and filament (FDM) minis?

Great question! And the answer is that, in 99% of cases, yes. Good acrylic primers for scale modelling, like the ones I recommend from specialist brands, are designed to work brilliantly on both resins and the typical plastics used in FDM (PLA, PETG, etc.). These are the ones I've tested across my entire collection and they've never let me down.

The real hero here isn't the type of primer, but the preparation. Make sure the piece is spotless, with no dust left from sanding or finger grease. A thorough clean is far more crucial than the exact type of plastic.

Can you prime with a brush and still get a good result?

Absolutely. Although spray or an airbrush give you that ultra-fine finish almost effortlessly, priming with brushes is a completely valid technique. Sometimes, in fact, it's the only option if you live in a small flat or the weather isn't cooperating.

The trick of the trade is to thin the primer with a little water until it has the consistency of skimmed milk. It's better to apply two or three very thin coats, letting them dry properly in between, than one thick coat. This way you avoid brush marks and, most importantly, you don't fill in the fine details of the mini.

How long should I wait before painting after priming?

Here, patience is a virtue. Even though spray primer may feel dry to the touch in 15–20 minutes, I strongly recommend waiting at least a couple of hours before starting to add colour. If you live somewhere humid or it's cold, leave it to cure until the next day. Trust me.

Giving the primer that extra time guarantees it has bonded with the miniature and created a solid base. If you rush into painting too soon, you risk the base paint "lifting" the primer and creating a real mess. In this hobby, rushing is never a good idea!

Conclusion

And that's a wrap, folks! I hope that after this rundown you have a much clearer picture of why primer is your minis' best friend. It's not a luxury — it's the foundation that makes all your painting effort look great and last. Remember: clean thoroughly, choose the method and colour that suits you best, and apply thin coats. With that, you're already halfway there. Now go get those figures ready for action!