Curing resin should be the rewarding part, watching a glossy pour harden into something solid and glassy. But sometimes it goes wrong: soft spots, tacky finishes, cloudy layers, or even pieces that never fully set. These problems are more common than people think, and most stem from a few core issues.
Temperature is one of the main culprits. Resin prefers warmth, ideally around 22 to 25°c. Anything cooler slows the chemical reaction, leaving you with gummy surfaces or uneven cures. If your workspace is cold, try warming the bottles in a water bath before mixing or curing near a gentle heat source.
Mixing is another crucial factor. If the resin and hardener are not blended thoroughly (scraping the sides and bottom of your cup matters), uncured pockets can form. Always follow the manufacturer’s ratio exactly. Adding extra hardener does not speed things up; it can actually ruin the balance.
Humidity can also affect clarity. Moisture in the air reacts with certain resins, creating a foggy or milky appearance. A small dehumidifier helps a lot in damp workspaces.
Contamination from oily moulds, silicone residue, or even fingerprints can prevent resin from setting properly. Wipe everything clean before pouring and cover your piece during curing to keep dust out.
If a batch goes wrong, you can sometimes sand back the surface and pour a thin, fresh coat over the top, provided it is fully cured first.
Resin requires patience. Every mistake teaches you something about how it behaves.
