Setting stepper motor currents

My Omerod RS343 occasionally faults on stepping in the Y axis.

This only occurs on small moves and only occasionally but this still rogers the print.
I belive the stepper motor current can be increased in the firmware, does anyone have the details for this.
(The belt is correctly tightened and so is the pulley)
The Z axis stalled at low heights until I oiled the leadscrew, but this is not a problem.
Dennis Cowdery

Hi Dennis
Just edit this line in your startup config.g on your sd-card, or you can change the setting on the fly with this line in pronterface

M906 X800 Y800 Z800 E800 ; Motor currents (mA)

Erik

Look at config.g in the sys dir on the SD card:

M906 X800 Y800 Z800 E800

Motor currents in mA.


Kev.

Edit: Should've clicked post before going to look at my latest print shouldn't I.

Edited 1 time(s). Last edit at 02/27/2014 07:18AM by KP.

Dennis,

if you're using firmware prior to 0.57n by dc42, increasing the current alone won't help- there was a bug in acceleration/deceleration that made the motors try to make instantaneous direction changes without slowing down, and caused missed steps. Since this update I've been running at 100mm/s with no problems on prints that used to fail at 40mm/s (I'm also using higher accelerations now that direction change is smooth and higher currents to match).

I think 0.57q is his current build [github.com] , this also includes a fix that allows PWM control of an external cooling fan (the fan connectors are beside the extruder connectors on the duet I'm in the process of trying to mount a fan satisfactorily - I'm having to slow down some prints now to wait for the print to harden between layers...)

Cheers

Ray

I'm using 1000mA for the Y motor and still 800mA for the others. I considered increasing the current for the Z motor, but I reduced the Z acceleration instead, since there is no need for fast Z movement and I would rather reduce wear on the threaded rod.

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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].

Thank Folks.

Your help was appreciated!

Dennis Cowdery