CApnkirk1993

Hi everyone new to the forums here. I am working on a ultimaker 2 printer and I am in the process of adding a solution printer to the side of the printer head assembly. One of the problems I am running into is the ultimaker not knowing that I have made the assembly physically larger, causing the motors to try and keep moving the head assembly on direction while adjusting the build plate. Does anyone know how to tell the ultimaker that the box assembly is larger so that it recognizes to stop before the assembly hits the side wall of the printer?