Once dipped in the melted chocolate, each strawberry should take around 10-15 minutes to set.  The spider berries do require an additional 5-7 minutes to set as a result of adding the black spider web piping, totaling an average of 18 minutes for these not-so-spooky treats.   Make sure that you place your parchment paper-lined tray with chocolate-dipped strawberries in a cool, dry area of your kitchen while they set.