Short answer: sticky resin is almost always caused by a wrong ratio, incomplete mixing or a cold room. If it is evenly tacky everywhere, move it somewhere warm (about 75°F) for another 24–48 hours. If it has soft or wet spots, scrape them off and pour a fresh, correctly mixed coat.
| What you see | Likely cause | Fix |
|---|---|---|
| Whole piece slightly tacky | Too cold, or still curing | Warm room, wait 24–48 h |
| Wet or gooey patches | Unmixed resin scraped from cup sides | Scrape out, clean with alcohol, recoat |
| Soft and bendy everywhere | Wrong A:B ratio | Remove what you can, recoat with measured batch |
| Sticky surface only (UV resin) | Oxygen inhibition or weak lamp | Cure longer, wipe with alcohol |
If the ratio and mixing were right and it was just cold, it often hardens once warmed. If the ratio was wrong, the excess part never reacts and it stays sticky.
Over a uniformly tacky but firm surface, yes; a correctly mixed new coat usually cures over it. Wet or liquid spots must be scraped off first or they will bleed through.
Most tabletop epoxies are tack-free in roughly 12–24 hours at room temperature; deep-pour resins can take several days. Check your product sheet.
Usually unmixed resin from the cup walls, or moisture in the mold. Dry molds fully and do not scrape the last bit of the cup into the piece.
More tools: resin calculator · mix ratio by weight · cure time · mold volume · tabletop coating · pouring too thick
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