What is blushing? How do I remove it?

Blushing is a chemical reaction between the hardener, carbon dioxide, and water present in the air. Blushing will appear as a white wax-like film on the resin surface, that will yellow over time. Blushing will interfere with adhesion of subsequent coatings and is difficult to remove. To prevent blushing, avoid working in humid environments or areas where you are burning fuels (propane/butane heaters, vehicle exhaust, wood stoves, etc.). Avoid condensation by working several degrees above the dew point throughout epoxy application and cure.

If blushing does occur, you can attempt to remove it using a scrubbing pad with soap and warm water. Amine blush is water soluble, so several repetitions of the cleaning process with water changes will be necessary. Do not use solvents or sandpaper to remove blush.