Pretty sure I killed a UM2 board stepper driver. Any solutions?

[rshuck 0]

Long story short, I was placing a heatsink on the steppers because I had some in an appropriate size, and during the process I saw something arc on the X axis placement, but I am not sure what. Power was disconnected and the power was turned off, but I suppose one of the caps hadn't discharged. It seemed ok at first and the board initialized properly. I was then installing an RPi camera and went to manually move the x axis and felt resistance. I turned the printer on and tried to home the axis - Y works, X doesn't. I had another stepper available, and it doesn't turn when it should. I am assuming I killed the driver.

Do I have any option aside from replacing the board? I am not sure where to go from here and would prefer not to have to wait for fbrc8 to get them back in stock or get one of the cheap Chinese replacements.

[rshuck 0]

For what it's worth, when the stepper is plugged into the unpowered board, it still has physical resistance, but when it's unplugged there is no physical resistance. When I turn it by hand I can feel each step.

[Torgeir 93]

Hi rshuck,

Welcome to this forum. Sorry to hear this, but the high rotating resistance when the X stepper is plugged to the main board indicate a shorted stepper driver circuit.

It is possible to change this circuit, but it has to be done by experts with proper tools etc. Buying from China is a risk and also takes some time.

Maybe you can ask fbrc8 if they can advice a repair center for the main board? There should be lots of repair centers in US with this kind of capability, also the complete wiring for the board is open source and available for this use.

Good luck.

Thanks.

Torgeir.

[rshuck 0]

I figured that was the case. Fbrc8 will have some in stock at some point in the future, so I guess I am dead in the water until then. I don't suppose there's any way that I can re-map it in software to use the Extruder 2 line to replace X, is there?

[mdg_nl 0]

There is a option to re-map the pins in "pin.h"

https://github.com/Ultimaker/UM2.1-Firmware/blob/UM2.1_JarJar/Marlin/pins.h#L1159

 

#define X_STEP_PIN 25#define X_DIR_PIN 23#define X_STOP_PIN 22#define X_ENABLE_PIN 27#define Y_STEP_PIN 32#define Y_DIR_PIN 33#define Y_STOP_PIN 26#define Y_ENABLE_PIN 31#define Z_STEP_PIN 35#define Z_DIR_PIN 36#define Z_STOP_PIN 29#define Z_ENABLE_PIN 34#define HEATER_BED_PIN 4#define TEMP_BED_PIN 10#define HEATER_0_PIN  2#define TEMP_0_PIN 8#define HEATER_1_PIN 3#define TEMP_1_PIN 9#define HEATER_2_PIN -1#define TEMP_2_PIN -1#define E0_STEP_PIN         42#define E0_DIR_PIN          43#define E0_ENABLE_PIN       37#define E1_STEP_PIN         49#define E1_DIR_PIN          47#define E1_ENABLE_PIN       48

 

You just need to swap these pin numbers:

 

#define X_STEP_PIN 49#define X_DIR_PIN 47#define X_STOP_PIN 22#define X_ENABLE_PIN 48#define E1_STEP_PIN         25#define E1_DIR_PIN          23#define E1_ENABLE_PIN       27

 

X_STOP_PIN needs to be the same (it's the limit switch).

Edit:

Keep in mind:

The X stepper motor current is set by the E motor current settings !

https://github.com/Ultimaker/UM2.1-Firmware/blob/UM2.1_JarJar/Marlin/pins.h#L1214

I hope your Extruder motor can handle 1250Ma ?

https://github.com/Ultimaker/UM2.1-Firmware/blob/UM2.1_JarJar/Marlin/Configuration_adv.h#L207

Regards,

Marten

Edited February 15, 2017 by Guest

[Torgeir 93]

Great info Marten!

Yes the extruder driver can handle 1250 mA, no problem as all the drivers is same type/setup.

Thanks.

Torgeir

[SyntaxTerror 343]

If you know/can find someone with a hot air rework station and a bit of skill, a new A4988 stepper driver can be had from Farnell for less than 5 euros. It sure beats the price of a new main board.