First of all, make a copy of your actual postprocessor, because you can produce big troubles, including a big machine crash, depending how you modify it.
They are two tabs: "PostProcessor" and "Editor".
If you select the Editor tab, then you have one more option in the main menu: "File" / "Option" file settings -> select it.
You will see a list of keys: select "Machine kinematics"
Then you will have an option "Kinematics Model" with a pulldown menu under it.
Select the option corresponding to your machine ( 3 axis, 4 Axis head, 4 Axis table...) or, if you already have a machine's mtd (simulation) file defined, you can select "External MTD" and pick your machine's mtd file.
If you don't have an MTD machine's file, you can try with the examples located in "C:\Program Files\Autodesk\PowerMill 2018\file\examples\MachineData" and altr it to match your machine.
Anyway, don't forget that adding an axis to a postprocessor is a little bit like opening Pandora's box: You absolutely must fully test your PP ! As long as possible with a good simulation tools and some simple (simple = easy to read and to cross-check, not too basic with all axes aligned or only 0°-90° rotations and workpice origine at the machine's origin) test programs. Then go to the machine with no piece and no or short tools defined as long tools, then with a plastic dummy block to make sure that the coordinates are correct.
It's a big job if you have never done it before, but if you succeed, the result is just great !
Olivier
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