Bubbles in Epoxy

There are several ways and several types of bubbles. When bubbles appear in a freshly applied epoxy coating, the most common culprit is something called "outgassing". Outgassing is a site condition that allows air or gas from the concrete (or timber) substrate to escape in excess and cause blisters, craters, bubbles or pinholes this is called off-gassing and it results in air bubbles in the resin, sometimes hours after you have poured and torched. To help prevent this you need to pre-seal your work, prior to resining. If you are casting into molds, choose a resin that is designed for casting (the long 'open' time of casting resin is to allow bubbles to rise to the surface from such a deep casting. The shorter the set time the less time for the bubbles to get out of the system. Use a flame or IPA to release surface bubbles. Many of our non-toxic, FDA Food Grade epoxies require no special requirements as they are self degassing, but with some other normal resins the cold weather will hold bubbles when mixing (simply heat resin to over 25 deg C in hot water prior to mixing helps this)