Plastic glasses can become stuck together if they are still wet when stacked, or if the glasses have been stacked together for a long period of time. Separating the plastic glasses can be difficult and may require more than just brute force. To prevent plastic glasses from becoming stuck in the first place, dry each glass thoroughly before putting it away and do not force plastic glasses together when storing. Instead, loosely stack them from smallest to largest.
Fill a sink with enough hot water to cover the bottom three inches of the bottom stuck glass.
Place the stuck plastic glasses into the sink upright.
Fill the top glass with ice water and allow the plastic glasses to sit for 20 minutes.
Remove the plastic glasses from the sink. Pull the glasses apart while twisting.
Pour edible oil, such as olive or vegetable, into a teaspoon.
Angle the spoon so that the oil drips around the rim and into the bottom plastic glass.
Grasp the bottom plastic glass and pull it away from the others while twisting. Repeat for remaining stuck glasses.
Wash the oil from the separated glasses thoroughly before using.
Wedge a butter knife in between the bottom plastic glass and the one above it to allow air to flow and release the vacuum lock.
Pull the bottom plastic glass away while twisting.
Repeat for remaining stuck glasses.
Place the stuck plastic glasses into the freezer and allow them to sit for 30 minutes.
Remove the glasses from the freezer.
Tap the rim of the bottom glass with the wood handle of a hammer until the glasses separate.