Good advice Ray. I do the same although just using small scraps of 1/8" (3mm) plywood. When that isn't practical due to the thickness of the piece being cut I'll set my cut depth to .05 less than the board thickness. If I've used a 1/4" end mill to profile or pocket through then I'll flip the board over and use a 1/4" flush trim pattern bit in a small trim router to clean finish the cut and free the part(s).
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