I'm building a machine to print cement using an array of nozzles, currently three of them.
My goal is to move in a scanning-type fashion, moving over the print bed in straight lines, with the line of nozzles perpendicular to the motion. Then I switch the nozzles on/off where water needs to be deposited, kind of like a dot matrix printer.
The nozzles/valves accept a 3.3V and/or 5V signal to open. I'm using a Duet2 Wifi board, currently with firmware 2.03.
My question now is how to best configure the Duet. Currently I have it working for one nozzle: , I connected the nozzle to the FAN1 output, disabled the fan, set up a tool that uses extruder 0 and then using M571 made the FAN1 (=P21) to turn on with the extruder. Then with G0/G1 with a Ex.xx command, the fan will turn on.
However, as far as I could find, the Duet2 Wifi only allows two extruders to be defined (M563), so I cannot perform this trick for 3 nozzles.
I have read about laser mode, but I can also not find how to control more thane one 'laser' in that mode.
I have tried as well to use M42 to just switch the nozzles on/off in between move commands, but this results in a very slow switching. It needs to be bound the G0/G1 commands for smooth/fast switching.
Any ideas about the best way to approach this?