Hello, I would like to know if it is possible to advance an extruder command relative to xyz movement. In other words, I want the extruder command to start earlier than the XYZ movement.
Background:
I am working on a metal paste 3d printing process at school. It uses an inverted delta printer for the XYZ movement of the build plateform. A ram extruder with an electric linear actuator pushes the molten feedstock through a pipe and then through the nozzle. I use the step/dir E0 output of the MKS gen L v1.0 board of the printer to communicate with the Kollmorgen AKD drive that controls the servo motor of the linear actual (ballscrew Tolomatic unit). The feedstock if first degased to eliminate compressibility issues. I did a simple test which consists of two vertical lines and multiple horizontal lines in between the vertical lines to check is the extrusion starts at the correct location. There is a consistent gap at the beginning and overextrusion at the end. I think that there is a delay from the extruder command and the actual piston displacement. If there is a way to quickly add a delay between the extruder and XYZ movement in Marlin, I would be able to validate this. I don't have a lot of experience with Marlin so any help would be appreciated.
Thanks
Olivier
