In the aero space industry, design for manufacturing promotes machining predictions using finite element analysis during design. Today design and computational engineers often are far from integrated. The design tool in this paper couples the simulation of distortion effects due to machining with CAD, where knowledge of how to perform a machining simulation is captured within the tool. The tool system is governed by a UNIX shell script and uses Python scripts for pre- and post-processing purposes coupled to the finite element software MSC.MarcTM. The tool allows an engineer to estimate the distortion effects due to machining and is believed to help bridge the gap between design and computational engineers in the manufacturing planning stages of engineering design. By using tools like the one presented here, both component quality and accuracy of machining operation cost estimation can be expected to increase, since distortion problems can be solved or prevented already in the manufacturing planning stages of engineering design. Thus design for manufacturing is enhanced since redesign due to inferior manufacturing can be reduced.