So here I am at the last stage of my first guitar project in 25 years. A mockingbird neck through and can't seem to find what the slot size should be in relation to the string size. I use 10's which has string sizes of 10, 13, 17, 26, 36 and 46. Of course Stewmac doesn't have a nut file for every size and common sense tells me the slot can't be smaller than the string. So, my question is..... how much larger can the slot be than the string?