Welcome to the SeeMeCNC Community

hi, just finished assemblying my rostock max, and im having some issues:
As long as I print a straight line everything goes fine, but when trying to print a corner (for example the corners in the calibration cube) the motors start going all jumpy and making the hole machine move, wich leads to a misalignment and really really bad printing results, sometimes it even tries to print a new layer with the Z too low.
I´ve done all the axis calibration and also corrected the printer radius (it was a bit low in the center)
I´ve also ruled out the pulleys and belts, y actually took them away, and send a print confirming that the "jumpyness" is comming from the motors (all 3 of them).
I did turn down the speed moves to 5mm/s and still the same issue

so, don´t know what else to try

The printer is a rostock max standar and I did assembly it following Geneb assembly manual Version 1.07

I guess thats all
Thanks!

Check the connectors from the motors to the Rambo. The crimps have to be done perfectly and must fit fully into the connectors.
See the link below that discusses how the connectors should look:
http://forum.seemecnc.com/viewtopic.php ... 666#p16666

Eaglezsoar wrote:Check the connectors from the motors to the Rambo. The crimps have to be done perfectly and must fit fully into the connectors.
See the link below that discusses how the connectors should look:
http://forum.seemecnc.com/viewtopic.php ... 666#p16666

Thanks for the response, I just checked the conectors, all tight and in position, in fact I soldered each wire to its conector, any other idea?

Check your motor current settings in your configuration.h file (#define MOTOR_CURRENT {175,175,175,222})
You may have to adjust them. (Increase current but keep around 200 or so, less if you can but it sounds like they need increased.)
The first three are the X Y Z axis the fourth is the extruder.

Eaglezsoar wrote:Check your motor current settings in your configuration.h file (#define MOTOR_CURRENT {175,175,175,222})
You may have to adjust them. (Increase current but keep around 200 or so, less if you can but it sounds like they need increased.)
The first three are the X Y Z axis the fourth is the extruder.

Changed the values, increased: nothing, decreased: nothing...
these were the default values in my config:
#define MOTOR_CURRENT {195,195,195,195,0}

the weird thing is that it only does it while printing round sections, everything else goes fine

Any other forum members reading this and may have an idea, please step in and help this member.
I am out of ideas.

Maybe post a video of it happening?
Have you tried reuploading firmware?

Make sure your end stop wires aren't routed next to your stepper motor wires, when unshielded, minimizing the amount those stepper motor wires are with others (even each other) is a good idea.

Another thing to try is to turn your heaters off and do a dry/test run with repetier host to make sure the problem is still there.

here´s a video I took of one of the steppers doing a circular print code

http://youtu.be/Ivj5k-LT5Lw

lordbinky wrote:Make sure your end stop wires aren't routed next to your stepper motor wires, when unshielded, minimizing the amount those stepper motor wires are with others (even each other) is a good idea.

Another thing to try is to turn your heaters off and do a dry/test run with repetier host to make sure the problem is still there.

shielded the 3 axis motor wires and end stops, it did nothing... but then I did a "dry run" and the problem dissapeared, so, if my calculations are correct I should be shielding the wires to the extruder and also the ones to the bed, right?

I´ll be posting the results later on!

shielded all the wires, and it´s still doing it, however it does run perfectly smooth on dry run

When you said it works perfectly on a dry run the first thing that popped into my head was the power supply.
I believe in Dry Run the Hotend and heating bed are inactive and not drawing any current.
This makes me believe the issue is the power supply is incapable of handling the current draw when everything
is powered up and is causing the issues that you see. Sounds logical to me.

Eaglezsoar wrote:When you said it works perfectly on a dry run the first thing that popped into my head was the power supply.
I believe in Dry Run the Hotend and heating bed are inactive and not drawing any current.
This makes me believe the issue is the power supply is incapable of handling the current draw when everything
is powered up and is causing the issues that you see. Sounds logical to me.

I´ve just unplugged the bed, the 4th stepper motor and the hot end, leaving only the axis steppers plugged to the board, and nothing changed, so I guess is not a power supply problem

FIXED!
Long story short; in my first run after assembly I noticed that the extruder had the polarity inverted, so I "fixed it" in the EEPROM using negative parameters in the extruder speed and accel, that made the plastic go as it should... but somehow it get all the steppers all jumpy.
This time I inverted it in config.h (what I should have done from the begining)
Looks like everything is runnig good now, I´ll have to reassembly everything but I´ll do it with a big smile on my face

Thanks to all the heplers!

Problem solving. Brought to you by : Process of elimination. 'I wonder what this does.'

Good job on backtracking that. Sounds like some input restriction might be good for repetier, unless it isn't that is.

Good job for solving that problem, it had to be a hair puller.
I love to see members posting the solution to a problem, we all learn a little
from every one.