I have a Lulzbot Taz 6 that the y-axis is just stuttering. When moving the axis from the display in one direction it physically moves back and forth with horrible noise.
I have adjusted the belt - no change.
I have changed the motor out with a good one - still does the same grinding.
I have swapped the y-axis on the Rambo with a different axis and it stops and moves smoothly.
Am I correct to assume that my board has an issue?
Thanks
Sounds like a failing driver to me.
If you never use your secondary extruder, you can rebuild the firmware to use the secondary extruder stepper driver for Y motion and keep the machine going. I recently had to do a similar swap on mine when I shorted the primary extruder driver.
Sounds great!
Just need to figure out how to do that…
If you have no experience rebuilding marlin, it would probably just be easier for me to do the swap and compile it for you, but if you want to give it a go, I can help as well.
I have zero experience with it. Will take any help I can get!
Not a problem. I’ll try to get it compiled tonight and post a link here. All you will have to do is disconnect the second (E1) plug from the Rambo and plug the Y axis into it, and use Cura to flash the new firmware.
Will do! Thanks a million!
Here’s the firmware - (edit: wrong link removed). I’m not going to rewire mine apart to test, so there’s a possibility that the direction of the stepper needs to be reversed. This is easily done by rotating the plug going to the board or motor 180 degrees.
The firmware is still controlling it from the y-axis port and not the second extruder port.
What does the text at the bottom of the “Ready” screen read? I changed it to reflect the modification to verify that the new firmware is loaded properly.
Ok, looks like I posted the wrong link, just a sec, gotta log into another system to get the right one.
This (was not the right one - edited out)
YAY!!! No more grinding. And it’s going in the right direction. Thank you SOOOO much!
1 Like
Glad it was a relatively easy fix. Hopefully I’ll have the BTT Octopus board programming complete by the time either of us needs another stepper driver to rely on.
1 Like
…so I thought.
Now the bed isn’t heating and the extruder motor isn’t running. But the Y-axis works great 
Simple check on the extruder motor, make sure it’s up to heat first, or the firmware won’t let it move. I could see something being left over from the changes I did for my own easily having been overlooked, so I’ll check it again this evening.
As for the bed heat? No idea on that.
Re-load stock firmware and confirm that the extruder and bed heaters work.
I am. All this could be from my rewiring (and probably is). It’s on my to do list!
The extruder works with the original firmware, but not the new one. The bed is a whole different issue, but is worrisome. One of the connectors to the heated bed has melted when it tries to heat (this is the second time). Granted, I can work without a heated bed if the extruder would work.

I missed the digipot swap portion, so here’s the re-rebuilt firmware. You’ll still have to figure out your heater problem though, since that’s not a firmware issue: