I am making an alignment tool to help me get my material in the proper place. I just a piece of .2" thick plexi that fits inside of the metal base portion, on top of the plastic. I want to engrave with a diamond tip bit a simple grid on it so that with it in place I can see through it to the material below to line up. If I make a 6" x 8" grid will there be any problem running the tool to the limits of the x/y or I should make it a little smaller to keep from hitting the limits? Thanks