Whatif Extruder axis is not E?


So in CNC you can have any number of axis setup by various names. X,Y,Z,A,B,C. 3D printers use E. Is there anyway I can tell Octoprint (or the slicer if need be) that the Extruder's axis is called A?


Is this a problem or just speculation/curiosity?

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For it is an agreement that E is the extruder for 3D printing (in combination with T for tool select) and also that OctoPrint is made to work with 3D printers in very first place, I don't think that is is that easy so make changes to OctoPrint and/or the slicers to use another letter for the extruder or tool.


You might want to read through all this. Active work is being done to extend OctoPrint beyond just 3D printing.


I ended up writing a filter that changes E into A for my purposes. In my slicer (Simplify) there is no way to change the extruder from E to anything else. Come to think of it, I haven't seen a slicer that can at all.


Yes, it's a problem not just speculation.


So.. what's the problem? Or do we need to guess?


Lol, sorry.

My g-code intepreter has six axies x,y,z,a,b,c it does not support E. All of the commands that go to E should really go to Tool 1 or to A. that's the problem.


AFAIK, one of the gcode flavors in Cura supports A B C as extruders.


It does?! Sweet! I'll have to investigate further. Therefore if Cura outputs A as the extruder, the octoprint will honor it right?


octoprint don't care what's after G1/G0, it will pass the gcode to the printer so it's slicer/printer issue, not octoprint....

as for s3d, there is a postprocessor where you can replace all E in to A, look at scripts tab, "additional terminal commands..." field .. there you can {REPLACE ...} should be possible to replace all E to A ....

iirc cura's "mach3" flavor shoots A instead of E but that was broken for a while, should be fixed in latest version of cura .. look at the gcode if there is "Flavor: marlin" if you select mach3 in cura then it's version with a bug. (this is the bug report: https://github.com/Ultimaker/Cura/issues/4929 here's the permalink in cura how it handles extruders in mach3 flavor https://github.com/Ultimaker/CuraEngine/blob/b11420f9c59e6e6951e3577523ba764fbc7035d8/src/gcodeExport.cpp#L322 )