I post this piece in CNC section, as it deals with 5-axis setup but with FDM in mind.
I have a simple 5-axis FDM setup, 3-axis X,Y,Z plus Z-rotation and tilt of the FDM nozzle; and due to the actual setup I need to do an inverse kinematic (IK) calculation. I can add this IK to the firmware of Duet itself, but I also can post-process G-code from tool coordinates to machine coordinates (I just did this as an experiment).
- no change in firmware (no recompiling)
- simple profiling (change setup needs no change in firmware required), each setup/machine has its own profile (a JSON file describing the inv kinematics)
- simple calibration of actual (physical) offsets and angles
- machine dependent G-code
- another step to convert G-code
- risk of doing stupid things (e.g. running tool into the bed) as firmware doesn't prevent it
To any experienced CNC machinist and multi-axis wizard, what are your thoughts? I don't know how CNC industry in general deals tool vs machine coords/g-code, and I like to get to know some good practices. Thanks.
If you like to see the actual setup https://xyzdims.com/2021/02/08/3d-printing-penta-axis-pax-5-axis-printing-option/ (work in progress)