Ultimaker 2 - Error ER05 and ER06 - broken Z axis stepper driver

[andysayle 0]

Afternoon all.  I've been doing some refurb on my Ultimaker 2, new bearings, belts, hotend etc.  When I have come to use it again, it is coming up with the ER05 and ER06 errors about the Z axis.  I've done some digging, and noticed on the main board, the little stepper driver chip associated with the Z axis stepper motor, has got a chunk missing from it.  Presumably this is why the Z axis limit is considered to be stuck/broken, as the Z axis cannot move.

 

I have tested the Z axis motor using a standalone driver, and the motor is working perfectly.  The motor coil resistance is in spec, and also the limit switch is actually working correctly (using TP80 to check for 5V/0V when switch is used).

 

I have a V2.1.1. mainboard, and it has the hardware for the second extruder.  I was wondering if anyone has any compiled a custom firmware, that allows the use of the E2 driver to power the Z axis motor?  From what I can tell from the schematics, the only issue I can see, is that the Stepper driver Vref for the second extruder, is shared with the primary extruder, and therefore the Z axis current limit will need to be the same as the Extruder?

 

Thanks

Andy

Edited October 8, 2022 by andysayle

[gr5 2,167]

There would have to be 4 precompiled firmwares to swap with the 4 other stepper drivers (x,y,z,e).  

 

But it's not hard to build the firmware.  I posted detailed instructions and the instructions have been improved a few times and many people have followed them.  There are quite a few steps you can skip if you aren't doing simulation (which you don't need to do).

 

 

Regarding current - it's software controlled current control.  There is probably a pin you have to change for that but I wouldn't worry about it.  The current for the 4 axes varies slightly but not by much.

 

Next you need to know what to change and in which .h file.  You want to edit pins.h.  More info here:

 

The nice thing about the above post is it has the right pin numbers for the E1 driver so you just need to edit the Z related pins.

 

[gr5 2,167]

Looking at the schematic, both X and Y share the same current control and both E0 and E1 also share the same current control.

 

I wouldn't worry too much about the current.  If you build the "tinkergnome" version of the firmware (that's what I use on all my UM2 printers) then you get the added bonus of current control in the menu system (instead of having to rebuild the firmware).  I think?  I think it's there.  Either way you can control it using a gcode as well.  I document that somewhere on this forum (what gcode to use).

 

 

 

[andysayle 0]

That's fantastic, thanks for the help @gr5

 

I've gone through, and done a custom version of the firmware (actually quite easy, even for an Arduino newb like me!).  I've mapped the E1 driver pins to be the Z axis Step/Dir/Ena, and also set the "DEFAULT_AXIS_STEPS_PER_UNIT" for the Z axis to now be 400 instead of 200 (it looks like the normal Z axis driver is using 8x µ-stepping, whereas the E1 driver is fixed at 16x µstepping.

 

It's good to hear the current control doesn't need to be adjusted too much.  From the code, it looks like the defaul values are 1200 and 1250, so not enough difference to worry about, like you said.

 

Thanks again, I've got some reassembly to do now, before I can test properly, although an initial power up looks like the Z axis is driving correctly now 🙂

 

Cheers

Andy

[gr5 2,167]

1 hour ago, andysayle said:

although an initial power up looks like the Z axis is driving correctly now 🙂

 

oh good.  I thought maybe you got it backwards in pin.h from your wording, lol.

1 hour ago, andysayle said:

"DEFAULT_AXIS_STEPS_PER_UNIT" for the Z axis to now be 400 instead of 200

Ah - there is a jumper for the Z axis so you can do either 8 or 16 ustepping but that doesn't apply to E1 of course.

 

Be warned that you are only changing the default.  You will likely have to do a FACTORY RESET in the menu system of the UM2 in order to get that value made current.  I could be wrong.  Anyway it's a good idea to do a factory reset anyway.  Certain defaults are stored in a special spot in the eeprom that doesn't get erased when you update the firmware.  Newer versions of Marlin know where the older values are stored but if you go backwards in firmware versions then those values get all messed up.  factory reset returns everything to defaults.

 

Or you can do the tinkerMarlin which is much better than ultimaker marlin and allows you to adjust steps/mm right in the menu.

[andysayle 0]

I'll take a look at the Tinker firmware, I've heard of it, but never tried it.

 

I've just done a couple of test prints (after a factory reset), and it seems to be working great.  The layer heights are spot on according to my calipers!

 

The only issue I have now, is that at the start of a print, the prime amount seems to not be enough, and the first 10cm or so of print is not happening, until the filament reaches the nozzle... 

[gr5 2,167]

Did you do a factory reset?  Many parameters/constants (likely including prime amount) are set back to default by a factory reset.

 

Also I think there is a bug possibly where if you end the print with an abort it retracts much too far and so you have to undo that either by hand (sliding in the filament) or with the MOVE option.