dual extruder motor programming
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i have a dual extruder setup which involves a nema8 motor which rotates via gear and racks to lower the current extruder into position and raise the other extruder out of the way, and vice versa. i am not sure how to program the slight motor movement every time the extruders change. any suggestions? thanks in advance
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I think you should be able to set those motors up as an independent axis and then use the tool change files to move them in and out of position when the tools are called.
Does that make sense?
https://duet3d.dozuki.com/Wiki/Gcode#Section_M584_Set_drive_mapping
https://duet3d.dozuki.com/Wiki/Gcode#Section_T_Select_Tool
https://duet3d.dozuki.com/Wiki/Macros#Section_Tool_change -
thank you phaedrux for your quick reply. if i understand you correctly I first set up the motor as an additional axis. Then start up the tpostn.g file in the system editor, and indicate there the change in the motor for both extruders to take place when there is a t0 or t1 in the gcode. Is that correct? thanks again for your insightful response.
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Yes that is the gist.
The additional axis for lifting and lowering the head will need to be homed in some way. Either an endstop or stall detection against a physical stop, or manually setting position with G92.
Then the motion would be defined in the tool files. Which tool files you use will have to be worked out for your needs. Do you want to tool to drop into position when selected and raised when deselected? That will be up to you, I can only imagine since I haven't seen the mechanism first hand.