https://forums.autodesk.com/t5/machining-discussions-forum/drilling-aluminum-full-or-partial-retract/m-p/6098767#M4483 Tapping in a different machine then where the holes were drilled is tricky one. Make sure you really measure it out well. If the tap is just a little off the holes centre you might be breaking them like matchsticks. Sat, 31 Oct 2015 15:53:38 GMT Laurens-3DTechDraw 2015-10-31T15:53:38Z