Small motions missing

netzmark

Hi,

My A5 has replaced original drivers with TMC2208, and the bearings with IGUS to get it more silent.

If I do the jogs like that with Pronterface or TFT, every second 0.1mm on Y motion is not performed.

If I do one by one the jumps +/-0.1 (forward and back so) any motions is not done at all.

X and Z axes make each single move without problems.

So I don't know is it some issue of my upgrade or settings, or normal result of the Marlin operationing.

There is some theory that small moves are accumulated byt the controller to don't do so small jumps. But only Y??

I don't remember how it was when the printer was unmoded. But I don't like this behaviour...

So I need an information, I hope someone could check it for me, how it is in your machines.

Stephen Todd

Just checked my A3s that has updated community firmware, but original stepper drivers, and LCD panel lets me move z, y, and x in 0.1 mm movements both directions

I've no experience with TMC2208 stepper drivers - but I know they have no physical reference voltage adjusters - they are set in firmware - have you set them correctly?

netzmark

Thanks Stephen.

You're right. There is voltage adjuster working as limiter and specific current is set by the firmware settings.

I thought I did it correctly but apparently maybe not.

Earthbound

I have TMC2208 drivers on my A5S. I run X @ 800ma, Y @ 850ma, and Z @ 925ma.

Sounds like the microstepping is not programmed to the correct value. Getting a report via gcode M122 might reveal something.

netzmark

Hi!

I have both X and currents set to 800mA (Z is original 4988). Changing the Y current between 600-1400 gives nothing positive, just the moves are more dynamic (strong) but still every second is "nothing" or almost nothing.

Thx for pointing on microsteps but it seems to me there is set 16. I will make sure tomorrow when sit at the printer.

netzmark

(both X and Y)

netzmark

@Earthbound

Something looking strange?

        X    Y

Enabled        true    true
Set current    800    800
RMS current    795    795
MAX current    1121    1121
Run current    25/31    25/31
Hold current    12/31    12/31
CS actual        12/31    12/31
PWM scale        14    14
vsense        1=.18    1=.18
stealthChop    true    true
msteps        16    16
tstep        1048575    1048575
pwm
threshold        6    6
[mm/s]        1642.62    1642.62
OT prewarn    false    false
OT prewarn has
been triggered    false    false
off time        5    5
blank time    24    24
hysteresis
-end        2    2
-start        3    3
Stallguard thrs
DRVSTATUS    X    Y
stst        X    X

Earthbound

Are your TMC2208 drivers plug-in modules? The settings look fine above, but module might not be using those settings if it is set to operate in standalone mode. Can you swap modules between X & Y (or Y & Z) to see if the issue moves with the module or remains on the axis?

netzmark

They are not standalone set and they are rather using those settings. At least I can change the current using some M-code (M906 if remmeber well) and I see the difference in working.

Drivers are in sockets, that is the plan to swap them and find the difference. Just wanted to collect any tips before begining to disasemble the printer, and with hope that I don't need it maybe :-).

I'll keep you informed when swap them, after the weekend.

Thx for help.

netzmark

Hi.

@Earthbound, so I have unscrewed the beast and swapped motors x with y.

Conclusion:

- motion of X direction are made always good no matter its motor is connected to the x or y slot. So both drivers or Marlin controls are set the same for X and Y (as expected but confirmed now).

- motion of Y direction are always made wrong, minimal one by one repeatable move is 0.2mm. If I do 0.1mm moves, every second is strong (normal) and the motions between are weak (let is be they are 0.01 instead of 0.1). But M114 says it is always done 0.1mm, so again - it's not any Marlin's algorithm.

Earthbound

With diligent swapping of connections and parts, you'll be able to deduce the specific cause.

Marlin config seems to be validated at this point.

If it is a problem of weak microstepping, the cause could be
driver module
control board (socket, PCB trace, solder joint, etc.)
cable from board to motor
motor

netzmark

Everything looks to me it's the motor. Or both drivers are working wrong, but small chance I think.

Continue searching...

netzmark

It looks the culprit are my bearings being too sticky, improving it.

Samuel Pinches

I had issues too with IGUS.