I used to have trouble removing all traces of glue from inside corners. My solution is to take a regular glue brush (also called a flux brush) and trim the bristles to a length of about 1/4″ with a razor knife. After wiping up most of the squeeze-out with a cloth, I dip the shortened brush in water and work the remaining glue out of the nooks and crannies. It helps to rinse the brush out frequently.
-Donald Cooper
