3D Print Prep
Wash, cure, and clean a 3D print properly so paint bonds instead of peeling — the step that saves the whole project.
A 3D print needs one extra step before it can be treated like any other model, and skipping it is the single most common reason a printed mini sheds its paint. Resin prints come off the printer coated in uncured resin — an invisible grease that no primer will ever bond to — so we wash it off in isopropyl alcohol and give the model a final UV cure. FDM prints carry fine layer lines instead, which we knock back so they don't telegraph through every coat. Five minutes of prep here is the difference between a paint job that lasts years and one that fingerprints off at the first game.
Best For
Recommended Paint Types
Step-by-Step
Wearing nitrile gloves, submerge the print in isopropyl alcohol (91%+) and agitate for 2–3 minutes, working an old soft toothbrush into the recesses, undersides, and support-scarred spots where uncured resin hides.
Rinse under running water and inspect in raking light: any glossy patch is uncured resin still clinging — scrub it again until the whole surface reads evenly matte.
Cure the print for 5–10 minutes in a UV cure station or an hour of direct sunlight, turning it halfway so every face gets light.
Clip any remaining supports flush with fine snips, shave the nubs level with a fresh hobby-knife blade, and you're ready to prime with your usual primer.
If It Goes Wrong
If primer beads up or crawls on the surface, there's still uncured resin underneath — stop, strip the primed patch with isopropyl, re-wash, re-cure, and re-prime; if a thin part warped during curing, dip it in hot (not boiling) water for 20 seconds, bend it true, then hold it under cold water to set.
Variations
FDM prints trade resin residue for layer lines: we sand the visible stripes with 220-then-400-grit paper, or brush on a thinned coat of filler primer, so the lines don't telegraph through every coat of paint.
Pro Tips
Buy a jug of 91%+ isopropyl alcohol and a cheap lidded container — it's reusable for many washes.
Raking light (a torch held almost parallel to the surface) reveals glossy uncured patches instantly.
Cure AFTER washing, never before — curing locks the residue on.
Support scars hide best on surfaces that will be textured anyway: bases, cloaks, fur.
Common Mistakes
Priming an unwashed resin print — the paint peels off in sheets within weeks.
Handling uncured resin bare-handed — it's a skin sensitiser; always use gloves.
Boiling-water warp fixes — hot tap water is enough; boiling softens fine detail.
Sanding resin dry without a mask — wet-sand or wear protection.