switching stepper from 8825

Hello,

I was wondering if there could be a solution to switch between two steppers connected to one pololu 8825. The context is simple : double head printer ! When we extrude one head, we never extrude the other one. I just imagine we could win one driver if we could switch the two steppers with some control card and modify the firmware to use this new setting ?
This could be usefull when we want to have two heads with a simple control card having only 4 stepper drivers ?
Thanks for any idea

---

the Smartrap project

[smartfriendz.com]
[www.thingiverse.com]
[reprap.org]
[github.com]
doc assemblage: [reprap.org]
NEW: Forum smartfriendz: [smartraptalk.smartfriendz.com]

You will need to turn off the power to the driver when you switch the motors, otherwise the driver will be damaged. This has come up before, but I haven't seen anything done with it.

Using a controller that has two E stepper drivers will be easier, since they're already available.

I think the circuitry to switch the motors and the software changes are harder to implement than a second extruder driver wiring.

Ho ok. thank you very much.. I think I agree with you. pololu are so cheap now.. It was just in case i've missed a very simple solution for people having a mini card with only 4 stepper drivers .

Thank you

---

the Smartrap project

[smartfriendz.com]
[www.thingiverse.com]
[reprap.org]
[github.com]
doc assemblage: [reprap.org]
NEW: Forum smartfriendz: [smartraptalk.smartfriendz.com]

Quote
smartfriendz
Ho ok. thank you very much.. I think I agree with you. pololu are so cheap now.. It was just in case i've missed a very simple solution for people having a mini card with only 4 stepper drivers .

Thank you

Some time ago, somebody suggested using a single stepper motor in a double extruder, with a servo selecting which of 2 filament paths the extruder was driving.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].