Where to Put the Stress on the Word "Grimace"?

After hearing our conversation about how dictionaries decide on a preferred pronunciation, and specifically about how to pronounce aioli, Vern from San Diego, California, wrote to say that a friend once made fun of him for pronouncing grimace with a stress on the second syllable. But when they finally looked it up in a dictionary, they found that indeed grimace can be pronounced either of two ways. This is part of a complete episode.