I have been running various projects and found something out about myself...I am not a painter. I have been using Pine with great results then I tried MDF with amazing results (I will be posting pics shortly) I read where someone painted the board then routed. I painted my MDF black and tried to route, got clear board sensor. Went on forum and read about keeping sensor clean and it might not pick up dark board to put on masking tape. I have a vinyl sign shop so I have access to large masking tape. I covered entire board with one piece of tape, trimmed edges flush and still will not cut. Put in pine with same project to see if it was a dirty sensor; cut perfectly. Can someone tell me what I could try. Don't know if it makes a difference 8" x 24" 3/4" mdf painted with flat black latex paint.