I'm in the process of building a panel cutting sled for my 3650. I'm using a plan from Woodcraft Magazine that calls for the miter bar to be of UHMW material, which I purchased at a local woodworking supply store. My problem is that the bar will not stay straight when I attach it to the 3/4" MDF with 1 inch #8 screws. After putting in only 4 of the dozen or screws called for in the plan, I test fit it only to find the miter bar won't go into the miter slot very far without binding. The plan tells you to bore the pilot holes on a drill press, which I don't have yet. I used a hand drill. I suspect that is my problem, and I need to be drilling at an exact 90 degree angle. My thought is to put a shallow dado into the MDF for the miter bar, and then screw it into the sled base. Any thoughts or other suggestions?