Thanks, everybody!. I suspected my endmill because I used my 1/4" 3 flute endmill and it cleaned up everything perfectly. I was using the 1/8" 2 flute endmill from Carbide 3D. Is it an upcut?. Will test others. @neilferreri What is a spiral “o”?. I was starting to get too confident and took the GWizard numbers as gospel and just went ahead and started a job. Lesson learned. When using a new material you haven’t used before, test, test, test!!!