MakerGear Forum

Hey guys, I'm tinkering with a dual extruder setup. Finally got my second hotend in and was going to do some testing, but when I go to retract/extrude my second motor just kind of vibrates and doesn't turn at all. I've tried tinkering with motor currents in Marlin, but it hasn't changed the result...it just vibrants more or less vehemently.

Any ideas?

Thanks,

Lon

I've proven it's not the motor itself by connecting that motor to E0 and extruding just fine.

Sounds like a bad stepper driver, which is unfortunate because there are only five of them on the RAMBo and you need all of them for the dual extruder configuration. Stepper drivers are actually fairly difficult to damage, so it could be something simple like a bad solder joint.

Tim wrote:Sounds like a bad stepper driver, which is unfortunate because there are only five of them on the RAMBo and you need all of them for the dual extruder configuration. Stepper drivers are actually fairly difficult to damage, so it could be something simple like a bad solder joint.

I bricked two RAMBOs (which Ultimachine fixed for free, which is amazing, and I am buying most everything from them from now on) by knocking off the "CFx" capacitor near the driver. Apparently its a low-frequency blocking cap and is kind of important to be there.

So I think I've just proven that it's not my Rambo (and by extension the firmware). I connected the motor that was originally on E0 to the E1 wiring and it worked. Which would mean that the driver is doing the right thing.

The only thing this leaves is the wiring itself (a brand new harness). I think?

-Lon