Cloudy or Milky Result — Causes and Fixes

A cloudy, misty, or milky appearance in cured or curing resin almost always comes down to one of two causes:
cold resin, or amine blush on the surface. Both are common, both are fixable, and neither means the batch is
ruined.

Cause 1: Resin or hardener was too cold when mixed

If your resin looks misty or milky as soon as you mix it — before it's even poured — the resin or hardener
was likely too cold. Both components need to be within their recommended working temperature to combine
cleanly.

Fix: Warm the bottles before your next attempt. Sit them in a bowl of warm (not hot) water for 10–15
minutes with the lids sealed tightly so no water gets in, or place them a couple of feet from a low heater.
Aim for a workspace and resin temperature of 21–24°C (70–75°F).

Cause 2: Amine blush on the cured surface

If the piece cured clear but now has a greasy, waxy, or hazy film on the surface, that's amine blush — a
normal side effect of epoxy curing in contact with moisture in the air. It's more noticeable in cool, humid
conditions.

Fix: Amine blush is water-soluble. Wash the surface gently with warm water and a mild soap, then dry
thoroughly. This does not affect the strength or clarity of the resin underneath — it's a surface-only effect.

Preventing it next time

• Keep your workspace within the ideal temperature range for your product (see the Mixing Ratio article for exact ranges per product).
• Avoid pouring in very humid conditions where possible, or improve ventilation/dehumidify the room.
• Warm resin and hardener before mixing if your workspace runs cool.

Related articles

• Mixing Ratio — How to Measure Resin and Hardener Correctly
• Bubbles — Why They Appear and How to Remove Them
• Sticky or Soft Result — Troubleshooting Incomplete Cure