topic_solved desperate, about to give up

printingmark

Hallo everybody,
i am beginnning to get desperate
trying for more than a week now, got help here a few days a go it workt for 2 prints and now every time i want to print ik starts at a differend place on the bed
i have a ender 3 pro, bed is 235x235 it has a bltouch, i am not verry technical, so please be patient with me config.json

if you press home all, and run G0 X120Y120 and repeat it a few times does the printer go to the same position each time?

unless the slicer is set to do some randomization to spread print surface wear you'll probably be loosing steps some how. low motor current/high friction, slack in belts, grub screw on drive pulley loose etc?

printingmark

@bearer every time i press home or G0 X120Y120 it is going to a differend place
the belts and grub screw ore i think oke
but i have now idea how to check the motor current

@printingmark said in desperate, about to give up:

but i have now idea how to check the motor current

according to your config.json its set to 400mA. idk what the nominal value for the ender 3 motors are but it sounds a bit low to me.

but you'd want to check your config.g file on the printer, the lines that say M906

https://duet3d.dozuki.com/Wiki/Gcode#Section_M906_Set_motor_currents

hang on, if the printer goes to a different place when you press home, its probably your home-all.g file that is the problem.

whosrdaddy

@bearer no you are on the right track, motor currents are way too low.
@printingmark try setting 1000ma for the xyz motors and 1300ma for the extruder motor.

printingmark

@whosrdaddy done that but it didnt helpconfig.g

i'd start by going over everything that is needed to make the printer home correctly.

this is for the maestro board, but most of it applies to the wifi as well

https://duet3d.dozuki.com/Guide/Ender+3+Pro+and+Duet+Maestro+Guide+Part+3:+Commissioning/39#s145

steps 3 through 6 should help.

printingmark

@bearer i will try, thanks

printingmark

for the moment all is working, thank you verry much all for the help

RS

@printingmark @whosrdaddy If memory serves me well, 1000 mA is too much for the Ender's stock motors.
I have the following currents: X/Y/Z=725 mA, extruder=850 mA.
That's within the motor's specifications (around 80-85% of max current, I believe), and works well.

whosrdaddy

if i'm not mistaken, the Ender 3 motors are rated for 1300ma and the extruder 1700ma, so 1000 and 1300 (a bit under 80%) should be no problem.Offcourse, if it works with lower currents, that's even better

RS

@whosrdaddy: Unfortunately I don't have any kind of official documentation about the Ender 3's steppers. The source I'm working from is this: https://gist.github.com/knoopx/e6c40a009e796203b93a75a3ed6a5ab8
Those currents work, and the steppers don't get too hot, so I'm happy.

But if anyone has other, more official sources, I'd be interested.

whosrdaddy

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printingmark

this morning it started all over again,repeated all stps no succes

printingmark

config.json

jay_s_uk

Can you share the config.g file instead please? The config.json is generated from the RRF config tool and then not adjusted again.
Can you also supply your homeall, homex, homey and homez files?

printingmark

homez.g homey.g homex.g homeall.g config.g

JoergS5

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droftarts

@printingmark if it’s not homing to the right place, are you sure your Endstops are plugged in correctly? Sounds like X and Y may be swapped.

Ian

printingmark

@droftarts i will check thanks

printingmark

@droftarts you where on the right track,one of the endstops was broken i saw movement in it while checking te connection
thank you

Karma

@printingmark Mark, I would suggest that you look at the following

M566 X1200.00 Y1200.00 Z24.00 E300.00 ; set maximum instantaneous speed changes (mm/min)
M203 X30000.00 Y30000.00 Z300.00 E1500.00 ; set maximum speeds (mm/min)
M201 X500.00 Y500.00 Z100.00 E5000.00 ; set accelerations (mm/s^2)

I beg anyone to please insure that I am giving the correct information and help for him. I am very new the REPRAP Firmware. Mark, please change that code listed above thats in your config.g file to the following

M566 X600.00 Y600.00 Z12.00 E150.00 ; set maximum instantaneous speed changes (mm/min)
M203 X3000.00 Y3000.00 Z30.00 E150.00 ; set maximum speeds (mm/min)
M201 X500.00 Y500.00 Z100.00 E500.00 ; set accelerations (mm/s^2)

The way you described your problem makes me feel like your stepper motors are skipping big time. I had this very same issue and I had to basically lower all those values down to almost nothing. After changing those valves listed above, my printer started to work like a champ. Produced some nice prints.

I own a Tevo Black Widow. I know you said you own an Ender 3. Those numbers I listed above for you to change will not hurt anything at all. But you can play with them so they fit your printer. I am only suggesting those numbers as a guideline to start at.

Keep us posted on your success.

Shawn B. aka Karma