Dual extruder with gear shifting I am planning to upgrade my printer with a second extruder. Since my printer is a Tronxy X8 it's frame is not exactly vibration resistant, so I'd like to keep the print head weight down. At the same time I really don't want a Bowden setup.
I came up with the idea of making a dual extruder driven only by a single stepper with a gear shift setup that switches the stepper between the two extruders.
The idea seems simple, but googleing didn't turn up anything else.
Is there anything I am missing that would would make such a setup unfeasible?
Did anyone else build something like that?
A clarification, because it came up in an answer:
What I imagine is this:
One stepper motor is connected to a gear shift system that is either connected to Extruder A or Extruder B, depending on the gear. When shifting it just connects the stepper motor to the other extruder. So it is still similar to a regular direct driven dual extruder system, except that it only uses a single stepper to drive two extruders, each connected to it's own hotend.
You'll need a custom firmware.
Yur custom firmware will have to react to the &quot;Change extruder&quot; command differently than a normal firmware: instead of just swapping to a different extruder, you'll need to perform some operations to alter the gearing (possibly a solenoid?), and possibly include some kind of &quot;break&quot; to make sure that the filament is not slipping back without the extruder attached. However, there already is a setup that pretty much does this: the Prusa MMU2 uses something similar. The MMU does use a Bowden setup, but you could use Bowden and direct drive in combination, especially if both motors run in sync.