Assembly & Prep: Getting Your Miniatures Ready to Paint

Hey again, friends. Let's talk about the step that everyone wants to rush through and nobody wants to make a video about. Assembly. Prep. The stuff that happens before your brush ever touches the model.

Here's the thing. I've been on both sides of the fence with this one. On one hand, I genuinely enjoy sitting down with a couple of models, putting on a podcast (something like Trapped Under Plastic), and just quietly building. It's relaxing. On the other hand, when I've got a big pile of models staring at me and I think about how long it's going to take to clean every single one of those stinking mold lines... I just can't. Not going to do that.

So over the years, I've tested all sorts of tools and techniques for building models efficiently. I've timed myself. I've compared results. And I've landed on a process that's both fast and clean. Whether you're building five models or 120 zombies (yes, I did that, and yes, it was a bit stupid), the steps are the same. The only variable is how much of your life you're willing to dedicate to plastic.

This guide covers the full prep pipeline from the moment you crack open a box to the moment your model is ready for paint. Each section links to a deeper guide if you want the full breakdown on that topic.

Cutting Models From the Sprue

Every Warhammer model comes on these plastic frames called sprues. First job: get the pieces off without destroying them. This is not rocket surgery, but the tool you use does matter.

I've tested everything from basic edge clippers from the hardware store to those fancy $60 luxury brand nippers. Here's what I found. Those cheap side snips with a flat edge from your local Home Improvement store? They work just fine as an entry point. They're a couple of bucks and they get the job done. The high-end luxury nippers are extremely sharp and leave almost nothing behind, which saves you cleanup time later. But they're also brittle, so only use them for snipping small bits off sprues. Keep a cheap pair around for the heavy-duty chopping.

One trick that makes a real difference: don't clip flush to the model where it meets the sprue. Leave a tiny bit of extra plastic attached. If you cut right where the piece connects, you risk gouging into the model itself. That gouge is much harder to fix and it'll show up on your paint job later. Instead, clip a little away from the model and trim that nub with a sharp hobby knife. Clean, flush finish every time.

If you're building a lot of the same models (like, say, 120 zombies), open all the boxes and batch-clip identical pieces. Building the same model 16 times in a row goes much faster than building 16 different ones. Every couple of seconds you save per step really adds up by the end.

Mold Line Removal

This is the step that separates a good-looking model from one that makes you wince every time you look at it after it's painted. Every single piece on your sprue has a mold line running all the way around it. Think of it as the equator around the Earth. That imaginary line is your mold line. It may change slightly with the surface, but it's always there on every piece you cut off the sprue.

I tested four different tools head-to-head with a timer running: a sharp hobby knife, a dull hobby knife, a machined dental-tool-looking thing from Monument Hobbies, and a double-sided sanding stick. They were all close, but the sanding stick won. The rough side makes short work of leftover sprue nubs, then you flip to the smooth high-grit side and fly over the mold lines. Because the stick is slightly squishy, it conforms to curves and tight spaces. One pass and done. No going back over the same section multiple times like you often have to with a blade.

That said, my true secret weapon for everyday building is a moderately dull hobby knife. I rotate my sharp blade into the dull role after a few months of use, then bring in a new sharp one. The dull blade is perfect for scraping off mold lines quickly without digging into the model or your fingers. It can get into any tight space and give you a crisp, clean finish.

For the full tool comparison with timing results, check out Mold Line Removal: Tools, Techniques, and the Fastest Method.

Gluing and Gap Filling

Warhammer models are plastic, which means we use plastic cement. Not super glue (save that for metal and resin). Plastic cement creates a chemical bond that melts the pieces together into one fused unit. Also, it won't glue your fingers together, which I do all the time with super glue.

I prefer Tamiya Extra Thin Cement with the brush applicator inside the cap. Super easy to work with. But here's where it gets good. Let me tell you about sprue goo.

I learned about this from my buddy Vince Venturella a few years ago and I've been tinkering with my own recipe since then. Chop up some extra sprue bits into small pieces and throw them into a jar half-filled with plastic cement. Let it sit overnight. When you come back, you've got a nice liquid goo. You can always add more sprue or more cement to get the consistency you want. I prefer mine thick.

Apply the sprue goo just like regular glue, but put on a little extra. When you sandwich your two pieces together, some goo squeezes out in the crack. Then hit that squeezed-out bit with pure plastic cement and smooth it over. It completely erases any gap or line. Nobody wants to take 100 built models and go through them with green stuff or milliput. With sprue goo, you get it done right away in the same amount of time it would have taken to build the model anyway.

If your models are snap-fit with those peg and hole systems, cut those pegs off. You don't need them. They only cause headaches and your model won't fit together right anyway. Use plastic cement instead.

Pinning and Magnetizing

Sometimes plastic cement alone isn't enough. Heavy metal models, resin pieces, and large components that bear a lot of weight can snap off if you just glue them. That's where pinning comes in. And if you want to swap weapons or heads between games, magnetizing is the way to do it.

These are slightly more advanced assembly skills, but they're not difficult once you understand the basics. A pin vise, some wire, and tiny magnets open up a whole world of options for your models.

For the full walkthrough on both techniques, head to How to Magnetize and Pin Your Miniatures.

Priming Your Models

The last step before paint hits model. Primer protects your paint from chipping and gives it something to actually grip. Bare plastic is slippery. Paint on bare plastic is paint that's going to rub off the first time you pick up the model.

Spray cans work best for most people. Shake that rattle can for at least a few minutes, then apply in sweeping motions. Never start the spray pointed directly at the model or you'll hose it down and obscure your details. I prime black because unpainted hard-to-reach areas just look like natural shadows. If I primed white, those spots would stick out like a sore thumb.

There's actually a lot more to priming than most people realize. Spray vs brush-on vs airbrush, black vs white vs grey, dealing with grainy or peeling primer, zenithal techniques. I cover all of it in the dedicated guide: Priming Miniatures: Everything You Need to Know.

Primer Color Theory

Your primer color isn't just a protective coat. It fundamentally changes how every subsequent layer of paint looks on your model. Black primer gives you built-in shadows but requires more coats for color vibrancy. White primer gives you punchy, bright colors but exposed areas look terrible. Grey splits the difference.

Choosing the right primer color for your project is one of those decisions that seems minor but actually saves you hours of work (or creates hours of extra work if you choose wrong).

For the full breakdown on how primer color affects your paint job and which to choose for different projects, read Primer Color Theory: Black, White, Grey, and Zenithal.

The Full Assembly & Prep Series

Here's every guide in this series, in the order you'd work through them on a real project:

Now get out there, build some models, and slay the gray.

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