Why BED TILT has not corrected the inclination?

General Discussion
1

Hi,

I have a doubt…

It is a CoreXY printer with 3 motors in z

always, before each impression I do the same procedure, which is:

1- homing
2- Bed Tilt
3- I separate in Z
4- Purge the extruder
5- And I print…

Except a few times, usually when I change some component that I run this other procedure

1- homing
2- Bed Tilt
3- Bed Mesh 7x7
4- Bed Tilt

But I think something is wrong, because I believe that, I attach the screenshot of the Mesh:

bed tilt crop
bed tilt crop1109×549 73.8 KB

It’s normal… if you look closely there is a lot of difference between the maximum and the minimum… but the most curious of all is that it forms like an inclined plane. Why hasn’t Bed Tilt corrected this a bit? If the side that is lower is raised a little, the bed would not be much more “flat”, not so inclined.

2

What does this do?

Is this done by a macro?

3

I have doubts that you have read the documentation :innocent:

Bed Tilt and Bed Mesh are not compatible and cannot both be used.
Ref: Configuration reference - Klipper documentation

4

i have some macros for do these movements

5

Mmm… It is not possible, I think I have made a mistake using the name of the commands.

1- Homing.
2- Z TILT (for Mainsail interface)
3- Move to center of bed
4- Re homing, but only Z (In case when I do (Z TILT) the Z is modified)

And only do Bed Mesh, time to time…

If this procedure is not correct. What would be the correct procedure with a 3 Stepper motors in Z.

P.D.: confirmed, I have not used the correct names… I don’t execute [Bed Tilt]… I do a [Z TILT], sorry. Mistake

6

It’s easy to mix them up.
bed_tilt:
https://www.klipper3d.org/Config_Reference.html#bed_tilt

z_tilt:
https://www.klipper3d.org/Config_Reference.html#z_tilt

7

First thing to understand is that z-tilt and bed-mesh are independent:

  • z-tilt tries to level your whole bed as a plane, usually by using 3 points
  • bed-mesh scans your bed to reduce deviations within this plane

→ This means if you build a mesh on a tilted plane, the mesh will store this. Later correcting the plane, will NOT correct the mesh.

Your screenshot looks like z-tilt has gone wrong and you build a mesh upon a tilted plane:

  • Delete the mesh
  • Verify the z-tilt settings, i.e. correct z_positions and points
  • Do z-tilt
  • Verify that z-tilt has worked correctly, i.e. by manually probing
  • Build a mesh
8

Hi,

I have tried to do that procedure described by @Sineos, and the same thing happens. The only thing I see that can be touched, but I don’t think it affects much, are the points where the leadscrews are… I attach my current configuration, some images, and the possible locations…

01 - Configuration

[bed_mesh]
horizontal_move_z: 10
mesh_min: 20,20
mesh_max:365,360
probe_count: 10,10
fade_start: 1.0
fade_end: 10.0
mesh_pps: 2,2
algorithm: bicubic
bicubic_tension: .35

[z_tilt]
z_positions:
	0,0
	200,400
	400,0

points:
	60,60
	235,370
	360,60

02 Mainsail mesh image

klipper actual mesh render
klipper actual mesh render1419×817 168 KB

03 Images of my bed

cama02
cama021353×740 59.1 KB

New mesh
New mesh833×717 107 KB

04 Possible chages in configuration of leadscrews?

[bed_mesh]
horizontal_move_z: 10
mesh_min: 20,20
mesh_max:365,360
probe_count: 10,10
fade_start: 1.0
fade_end: 10.0
mesh_pps: 2,2
algorithm: bicubic
bicubic_tension: .35

[z_tilt]
z_positions:
	-5,-5
	200,405
	405,-5

points:
	60,60
	235,370
	360,60

I don’t think that these slight changes in the position of the leadscrews will change the result much, the main problem is that the bed comes out “sloping”, it is not that it is bent at one point, or a corner… it has a fairly steep slope uniform…

Could it be a mechanical failure? (pj: of the motors, that they are not exactly the same and 1 of them advances a little more?)… I don’t think so

Any more ideas?

9

Z-Tilt is commonly known to work as it should, given that it is properly configured. Basically I see two possibilities:

  • Misconfigured Z-Tilt
    • I cannot comment on your settings, since I do not know the printer
    • Make sure that the z_positions are in the same sequence as your steppers, z / z1 / z2
  • Mechanical problem:
    • Maybe the probing is correct and your bed really is shaped like this
    • Other issues with the Z-Axes