Printer used to move to far

Basic Information:

Printer Model: Anet A8 Plus
MCU / Printerboard: BTT SKR 2/tmc2209
klippy.log

Fill out above information and in all cases attach your klippy.log file. Pasting your printer.cfg is not needed

Describe your issue:

I’m not home to get the klippy.log but I think I have everything close. When I initially installed octoprint/klipper I was going through all checks and everything was good except how far everything moved once commanded from the octoprint control panel. When I told it to move 10mm in any direction it would actually move 25mm and would continue that ratio no matter how far I commanded it. The only way I was able to get these almost dialed in by drastically changing my rotation distance in the config file. X from 32 to 80. Y from 32 to 79. Z from 8 to16. Can’t remember what I changed the extruder to. Is this a common issue that needs to b worked through when upgrading boards/ firmware?

Rotation Distance is defined by the mechanical components (pulleys, gear ratios; spindle lead etc.) of your printer. So if you did not change that there is something else off!
Only the feeder needs to be calibrated.
Maybe you changed the microstep settings or the full steps per rotation although this should result in multiples or integral parts of the former values.

Best is you get home and upload the klippy.log so we can check the parameters.

I planned on it. Just wanted to see if anyone experienced this before. I did get the pre made skr 2 config from the site and changed all the parameters to match the Anet A8 Plus config. That’s the only other thing I did to that config

40 is the correct rotation distance for X and Y on almost every consumer printer on the market. That translates to a 20 tooth pulley at 2mm pitch. Z is typically 8 for lead screws, but can vary on some printers. If you need 80 and 16, then you likely have your full steps per rotation misconfigured. It should be 200 for 1.8 degree motors, and 400 for 0.9 degree motors.

I’m also learning as I go but where would I reconfigure my full steps per rotation or see what they’re. I don’t see any one those parameters in the config file.

Really need to see your log file to help further.

This should be my klippy log. Appears just like the config. you will notice my changed rotation distances. Also if it helps I figured out today my printer specs if you can confirm my math
-1.8* stepper motors, so 200 full steps per rotation
-Belt pitch is 2mm and all pulleys (2 per X/Y axis) have 16 teeth. do number of pulleys change math?
So i should have 100 steps per mm, and a rotation distance of 32 for X/Y
klippy.zip (2.0 KB)

The default is 200 steps per rotation, so you shouldn’t need to change that.

You indicated you have 2209 drivers, but you haven’t configured them. If they’re running in standalone mode, you need to verify the jumpers to confirm your microsteps.

I should also note that if your printer is moving the correct distance with 80 steps per mm, then it’s not possible that your pulleys are 16 tooth. While those pulleys exist, they’re pretty rare. 20 tooth pulleys are much more common. The website for the A8 Plus confirms that they use 20 tooth pulleys.

Ugh I think I see where I messed up now. At the bottom of the BTT skr2 config there’s a section for the tmc2209s. Now I’m a little confused what to exactly do with it. Do I just add this to what’s already there, reverting back to original rotation distance, changing the name and leave diag_pin blank? Or remove everything and only have this for each axis?Also does run current mean adjust the pot on the driver? Thank you for shedding some light
#[tmc2209 stepper_x]
#uart_pin: PE0
#run_current: 0.800
#diag_pin:

Judging from your klippy.log you have multiple issues:

Rotation distance:

  • If you did not modify your Anet (e.g. 0.9° stepper etc) then your rotation_distance setting are wrong as @jakep_82 pointed out
  • Needs to be 40 for X/Y and 8 for Z

TMC2209 settings

  • Settings are completely missing
  • Ref to klipper/generic-bigtreetech-skr-2.cfg at master · Klipper3d/klipper · GitHub for a starting point
  • diag_pin is only needed for sensorless homing and should be left commented
  • run_current is set dynamically in the config block, the potentiometer is no longer used
  • Also refer to the BTT SKR2 documentation on how to set your board properly for TMC2209 usage

Yup I was agreeing with @jakep_82 and confirming what I overlooked. So my new config per axis should look something like this. If so I will confirm this later today.

[tmc2209 stepper_x]
uart_pin: PE0
run_current: 0.800
#diag_pin:
step_pin: PE2
dir_pin: PE1
enable_pin: !PE3
microsteps: 16
rotation_distance: 40
endstop_pin: ^PC1
position_endstop: -30
position_max: 300
position_min: -30
homing_speed: 20

Uhm, no!

Axes config section and TMC config sections are separate. Refer to the SKR example I posted above

Ok so just remove # from all lines in tmc2209 section of config? This is the most I’ve ever had to do with coding and I don’t see anything anywhere that says do this or that

Follow this logic for all axes and extruder:

[stepper_x]
step_pin = PE2
dir_pin = PE1
enable_pin = !PE3
microsteps = 16
rotation_distance = 40
endstop_pin = ^!PC1
position_endstop = -30
position_max = 300
position_min = -30
homing_speed = 20

[tmc2209 stepper_x]
uart_pin: PE0
run_current: 0.800
#diag_pin:

Be sure to also follow SKR-2/BIGTREETECH SKR 2 user manual.pdf at master · bigtreetech/SKR-2 · GitHub for properly configuring your SKR2

YES!!! thanks to you all my printer is finally up and running the way it should. Sorry for my ignorance with everything but we all start somewhere. I really appreciate the help.

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