Calibration madness

I have a question about calibration.

I have the Snapmaker 2.0 A350 and I am unable to calibrate the printbend sufficiently.

What I’ve tried so far:
I had to adjust the z offset by the specified mm when printing.

  • Auto calibration (first attempt), cold printbed: attempt to print -> 2.1 mm Z adjustment to the printbed
  • Manual calibration (first attempt), Kalters Printbed: Print attempt -> 2.1 mm Z adjustment to the printbed.
  • Auto calibration (second attempt), printbed ~ 70 degrees celsius: pressure test -> 1.3 mm Z adjustment to the printbed
  • Manual calibration (second attempt), printbed ~ 70 degrees celsius: pressure test -> 1.2 mm Z adjustment to the printbed.

After that I adjusted the sensor:

  • Print head set on the printbed with a sheet of paper in between.
  • Sensor loosened.
  • Sensor moved up and down until the red light shone.
  • Sensor screwed tight.

Then calibrated again:

  • Auto calibration (third attempt), printbed ~ 70 degrees celsius: pressure attempt -> 1 mm Z adjustment to the printbed
  • Manual calibration (third attempt), printbed ~ 70 degrees celsius: pressure attempt -> 0 mm Z adjustment to the printbed.

It is no longer necessary to adjust the z offset when printing, but on the left side the print head is too high (prints in the air) and on the right side is too deep (scratches in the printbed).

Why is there such a big deviation and how can I compensate for it?
How can I calibrate it sufficiently?
It seems that the values ​​of the individual (of the 9) measuring points are not saved or not saved correctly during manual and auto calibration.

Thanks in advance

Hey @Chris, what firmware is on your machine? There where some bugfixes about calibration in the last one (one week ago or so).

Btw, the calibration sensor should be calibrated to 1mm (thick like a creditcard)

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Hi.
Thank you for your reply. I double checked the version and I am currently on the version 1.6.1.0

  • controler : 1.6.0.0
  • touchscreen : 1.6.1.2

Thanks for the hint.
I just see that version 1.7.0.0 is available. I’m doing the update right now and I’ll see if it gets better :slight_smile:

I calibrated it with 1mm and it went straight to the print bed. Now I’ve calibrated it to 1.53mm and it’s almost where it should be.

What I noticed is that the sensor does not recognize the print bed at some calibration points (not always the same) and presses hard into it.

you could also check the following thread in terms of calibration issues:

there was the firmware update between,- i think there are several other threads about leveling problems.

Hope it helps!

Hi,

Looks like with latest FW problem still exists.
I can see that lines in the center are wide and thin (almost transparent) and on the sides they barely stick to surface.

Is there any way to force machine to compensate bed deviation during printing?

Usually the problem you’re describing (high in middle) is caused by improper assembly.
Is your bed frame installed properly? Should be nuts down.
Are you using the correct screws. Should be flathead so they’re flush.

You can also try tightening screws from inside to out, opposite sides (like tightening lug nuts on a wheel) or just using 4 center ones.

-S

this is pretty much the same issue i have, 6mo of back and forth with support have resulted in no clear answer - i have already proven on my machine (and it was replicated on snpamakers) that there is still something mechanically or mesh levelling thats an issue - the nozzle simply doesn’t travel in space at the right distance above the build surface. Now to be clear it mostly does - that’s why things like an 11x11 calibration, glass, etc help they are all Band-Aids to what I believe is a fundamental issue. For some these Band-Aids mask the issue to the point folks think they are fixes, for some us they do not).

If you haven’t done an 11x11 G1029 calibration i thoroughly recommend it, for me the difference is night and day compared to 5x5 touchscreen, YMMV.

Scyto, newbie here. I’ve been trying to follow the 11x11 calibration discussions but get lost in some of the details. I’ve seen one about using octoprint, which I don’t have. I’ve seen one about 7x7 since you can’t keep the bed hot long enough for a 11x11. Can you explain in simple terms how to do a 11x11 given the latest firmware? I’m currently doing the 5x5 with heated bed since that is in the firmware. I’m still getting spots where first layer, especially at the start of a line, that isn’t sticking well, pulling up a string that later gets in the way. I’d like to try an 11x11. Is it simply the G1029 P11 command? How can I do that with the heated bed on? Also, more general question: when I’m doing the 5x5, the first spot is at 10mm in the front left corner. But when it gets to the 5th spot, that spot is at about 260mm, not the right most edge (310?) and the rest are right down the 260mm line. Is that normal not to go to the right edge? A350 machine. Thanks!

You need to be able to get to the serial console (not over wifi).

You can us Luban and the USB cable for this if thats easier (its what i use despite having ocotoprint)

I have two Macros i use in Luban to make this easy on me, but you can also manually type them in the serial console.

My start macro looks like this:

G28 ;Home
G1029 P11 ;Set auto-level mesh to 11x11
G1029 S ;Save auto-level mesh configuration
G1029 A ;Start auto-leveling

you run these commands, wait for it to finish (it will measure 144 points on the bed; this will take some time, go make a cup of tea)
once it has measured all the points you manually use the Z+ / Z- buttons in luban to get the head to pinch the calibration card as you normally do - same tension you normally do (personally i moved the head in 0.02 increments for the last part).

once you have the head where you like you run the following macro or manual commands:

G1029 S ;Save settings
G1029 D0 ;Confirm auto-leveling is on.
M420 V ;Verify auto-level results
G28 ;Home

and you are done, what you can’t do is have the bed heated during this, the G1029 command disables that, i put a PR in to change this longterm and it seems to have been accepted, for some heat makes no diff, for others it seems to.

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