How to · Miniature painting
Priming a miniature, and why it decides everything after
Primer is the least interesting step and the one that most often wrecks a model. A bad prime cannot be painted over — it has to be stripped — and almost every bad prime is caused by one of three things that are entirely avoidable.
Acrylic paint does not adhere reliably to bare plastic, resin or metal. Primer is a coat formulated to grip the model and to give the paint something to key into, and without it paint lifts, chips on handling and rubs off the raised edges exactly where you least want it to.
It does a second job that matters more to how the model looks. A thin, even primer coat unifies a model made of different materials and colours into one surface, so the paint above behaves consistently. And the *colour* of that coat sets the value the whole scheme sits on, which is why the black-or-white argument is not merely preference.
| Primer | What it gives you | What it costs |
|---|---|---|
| Black | Instant shadows in recesses; forgiving of gaps in coverage | Colours go on dull and need more coats; bright colours may never reach full saturation |
| White | Maximum brightness and saturation from thin paint | Every gap and every mistake is visible; needs deliberate shading afterwards |
| Grey | A neutral middle that shows the sculpt clearly | Neither of the advantages above — the sensible default rather than the exciting one |
| Coloured | A head start when most of the model is one colour | Useless if the scheme changes; a specialist choice |
For a first model, grey. It shows the detail you are about to paint more clearly than either extreme, it is forgiving, and it does not commit the scheme to a particular approach before you know what you are doing. Black and white both have strong advocates and both are correct for particular styles.
Step 1: Wash the model first
Warm water, a drop of washing-up liquid, an old toothbrush, and let it dry completely. Casting release agents on resin and mould release on plastic both stop primer gripping, and this step is skipped constantly.
You will know it worked when: The primer meets the model rather than a film of oil.
Step 2: Check the conditions before you shake the can
Cold and humid are the two enemies. Spraying below roughly 15°C or in damp air is what produces a chalky, gritty finish, and it happens in a British garage for most of the year.
You will know it worked when: You find out before ruining the model rather than after.
Step 3: Shake for far longer than feels necessary
A full minute, minimum. Under-shaken primer sprays unevenly and cures badly.
You will know it worked when: Consistent spray from the first pass.
Step 4: Several very light coats, from about 20–30cm
Each pass should barely tint the model. The instinct is one covering coat and it is wrong — a heavy coat fills the detail you bought the model for and takes far longer to cure.
You will know it worked when: Detail preserved, and a surface paint will grip.
Step 5: Let it cure properly before painting
Touch-dry is not cured. Give it several hours, or overnight if it is cool.
You will know it worked when: Paint sits on the primer rather than lifting it.
| Surface | Cause | What to do |
|---|---|---|
| Chalky, powdery, rubs off | Sprayed too cold, or too far away — the primer dried before it landed | Strip and start again. Painting over this wastes the paint |
| Fuzzy or furry texture | High humidity | Strip. Wait for a dry day |
| Detail softened or filled | Too heavy a coat | Strip if the sculpt has gone. Thin coats next time |
| Shiny patches, paint beads up | Model was not washed | Strip, wash properly, re-prime |
| Sticky after hours | Too thick, or too cold to cure | Give it much longer somewhere warm before deciding to strip |
| Cracked or crazed | Incompatible primer over an existing finish | Strip. Check what was on the model before |
The judgement worth internalising: a bad prime never improves under paint. Every one of the failures above gets worse, not better, once colour goes on, and stripping a primed model costs an evening while painting a badly primed one costs the model.
Questions this guide answers
Listed so you can tell at a glance whether this is the page you wanted. HobbyHQ keeps one guide per question family rather than a page per phrasing.
- how do I prime a miniature
- what colour primer should I use
- why is my primer chalky
- why did my spray primer go fuzzy
- can I paint a miniature without primer
- black or white or grey primer
Sources for this section
- COSHH: Control of Substances Hazardous to Health (opens in a new tab) — Health and Safety Executive · Governing body · read — partly supports
Part of Miniature painting. Last reviewed 2026-08-14.