I have started cutting metal and printing parts for my next 3D printer, but now I realise that I don't have the slightest idea how I am going to address the software implications of my design.

The printer has a build stage that moves in X and Y with a bank of extruders moving only in the Z direction. When each extruder is needed it is moved to the index position and extended downwards slightly. The bank of extruders would be mounted on a turret or perhaps a sliding block - mouth organ style.

Does anybody know if this method is catered for in existing slicers, host software and firmware? At a minimum, some output is needed to get a stepper to move the next extruder into position. Extension of the selected extruder and retraction of the unused extruder would be done by a cam mechanism.

My reason for trying out an XY build stage is that any more than two extruders would have more mass than most build stages even with a build under way. Although I have bowden extruders on two of my previous printers, they seem less than satisfactory for softer materials such as Ninjaflex. I am hoping to start with three extruders and move to 5 with a digital depth gauge in the 6th position for bed leveling.

Mike

I know that Slic3r does this and suspect that Repetier does as well: you can configure slicing software to execute custom gcode to change extruders. You would need to customise the firmware to send the (I assume) servo commands to change the extruders on receipt of the correct gcode, however.

Repetier have an online configuration tool that will allow you to generate firmware for a custom number of extruders.

Thanks 3dkarma, I have looked at Slic3r for slicing and repetier firmware for control. They do seem to give enough that I can build on for a larger number of extruders, but I think that I will need to make a suitable extender to control the extruder swaping motor as well as the extruder motor(s). As only one extruder will be active at any one time, it will need to be able to swap the outputs from the driver to each stepper - something that causes pololus to blow up, hence the need to new hardware.

Mike