Printing in mid air after ABL routine

Zuru1

Hi,

I finally got the ABL feature working and ready to move to the next step,
but when I did my first test print, the nozzle is still in the air when the printer starts to print.
Simply the printer does not lower the nozzle after ABL routine.

My printer is a prusa i3 clone configured with repetier 1.0.0dev firmware.
For ABL, I use an inductive proximity sensor with a detection distance of 8mm.

Any clue to why this happens?

Thanks you

Repetier

Normally your z probe height is wrong when you are not where you expect to be. Change by difference. If it gets worse you have corrected in wrong direction.

Zuru1

Ok, I will do that.

Is there anything else that I need to add to my startup gcode other than G28 and then G32?

Repetier

G32 is normally not part of startup. G32 S2 stores rotation in eeprom so it is always present after homing. Only rerun it if you have changed something that might change rotation.

Hosts start gcode is normally empty and you should only add such commands in the slicer start code along with temperature settings. Some do generate suitable code already without extra code.

Zuru1

Thank you for the help.

I now managed to do a print and all was almost perfect besides for one new problem that I stumbled upon.
I already know that my left side of the heated bed is about 1 - 1.5mm lower than the right side, also according to the z hight obtained by the probe.
But when printing that difference shouldn't exist right, due to the ABL feature?
Simply the nozzle should be always be at given x mm away from the bed at all times, and not closer to the lower side while being away on the higher side.

Any idea on how to resolve this?
All do I need to increase my grid from 2 to 4 or more in order to resolve this issue?

Again, thank you for everything.

Repetier

Grid size is not that important for cartesian and flat bed. Just make sure you used G32 S2 so correction is stored in eeprom so it stays permanent. The command also returns the rotation matrix so you can see if it works. And you should see z axis moving when moving between high/low area.

Beside this 1.5mm difference is very much and you should try to reduce that hardware wise. The less software has to correct the better. After all bigger difference makes z move more, so more wear and it might even reduce speed if z axis is slow.

Do not enable distorion correction for testing at least. If you later see smaller bumps you might do that, but do it only if really needed.

Also note there are commands to disable autoleveling so do not use them!

Zuru1

Well I thought that I had missed or that there is some configuration to handled that.
I will adjust the bed manually so close as I can and see if that solves the issue.

Thank you

Zuru1

Well did the manual bed adjustment and got it this even

Echo:N1036 G28
Info:Autoleveling disabled
Z-probe:6.337 X:0.00 Y:0.00
Z-probe:6.351 X:0.00 Y:200.00
Z-probe:6.343 X:150.00 Y:0.00
Z-probe:6.342 X:150.00 Y:200.00
plane: a = -0.0000 b = 0.0000 c = 6.3410
Transformation matrix: 1.000000 0.000000 0.000010 0.000000 1.000000 -0.000030 -0.000010 0.000030 1.000000
CurrentZ:6.34 atZ:6.35
Info:Autoleveling enabled

The result is now that both on far left side(out of the rectangle) and right side (inside of the rectangle), the bed composition is totally ignored or not done at all.
What am I doing wrong?Been at it now for a week and nothing to show for it.My EEPROM configuration

22:28:00.519 : EPR:0 1028 0 Language
22:28:00.519 : EPR:2 75 250000 Baudrate
22:28:00.534 : EPR:3 129 5.786 Filament printed [m]
22:28:00.534 : EPR:2 125 14510 Printer active [s]
22:28:00.534 : EPR:2 79 0 Max. inactive time [ms,0=off]
22:28:00.550 : EPR:2 83 360000 Stop stepper after inactivity [ms,0=off]
22:28:00.550 : EPR:3 3 200.7748 X-axis steps per mm
22:28:00.550 : EPR:3 7 197.9782 Y-axis steps per mm
22:28:00.565 : EPR:3 11 800.6468 Z-axis steps per mm
22:28:00.565 : EPR:3 15 200.000 X-axis max. feedrate [mm/s]
22:28:00.565 : EPR:3 19 200.000 Y-axis max. feedrate [mm/s]
22:28:00.581 : EPR:3 23 1.500 Z-axis max. feedrate [mm/s]
22:28:00.581 : EPR:3 27 40.000 X-axis homing feedrate [mm/s]
22:28:00.581 : EPR:3 31 40.000 Y-axis homing feedrate [mm/s]
22:28:00.597 : EPR:3 35 2.000 Z-axis homing feedrate [mm/s]
22:28:00.597 : EPR:3 39 20.000 Max. jerk [mm/s]
22:28:00.597 : EPR:3 47 0.510 Max. Z-jerk [mm/s]
22:28:00.597 : EPR:3 133 0.000 X min pos [mm]
22:28:00.612 : EPR:3 137 0.000 Y min pos [mm]
22:28:00.612 : EPR:3 141 0.000 Z min pos [mm]
22:28:00.628 : EPR:3 145 200.000 X max length [mm]
22:28:00.628 : EPR:3 149 200.000 Y max length [mm]
22:28:00.628 : EPR:3 153 185.000 Z max length [mm]
22:28:00.644 : EPR:3 51 1000.000 X-axis acceleration [mm/s²]
22:28:00.644 : EPR:3 55 1000.000 Y-axis acceleration [mm/s²]
22:28:00.644 : EPR:3 59 100.000 Z-axis acceleration [mm/s²]
22:28:00.659 : EPR:3 63 1000.000 X-axis travel acceleration [mm/s²]
22:28:00.659 : EPR:3 67 1000.000 Y-axis travel acceleration [mm/s²]
22:28:00.659 : EPR:3 71 100.000 Z-axis travel acceleration [mm/s²]
22:28:00.675 : EPR:3 1024 0.000 Coating thickness [mm]
22:28:00.675 : EPR:3 808 1.250 Z-probe height [mm]
22:28:00.784 : EPR:3 929 5.000 Max. z-probe - bed dist. [mm]
22:28:00.784 : EPR:3 812 2.000 Z-probe speed [mm/s]
22:28:00.784 : EPR:3 840 150.000 Z-probe x-y-speed [mm/s]
22:28:00.800 : EPR:3 800 38.000 Z-probe offset x [mm]
22:28:00.800 : EPR:3 804 0.000 Z-probe offset y [mm]
22:28:00.800 : EPR:3 816 0.000 Z-probe X1 [mm]
22:28:00.800 : EPR:3 820 0.000 Z-probe Y1 [mm]
22:28:00.800 : EPR:3 824 150.000 Z-probe X2 [mm]
22:28:00.815 : EPR:3 828 0.000 Z-probe Y2 [mm]
22:28:00.815 : EPR:3 832 0.000 Z-probe X3 [mm]
22:28:00.815 : EPR:3 836 200.000 Z-probe Y3 [mm]
22:28:00.815 : EPR:3 1036 0.000 Z-probe bending correction A [mm]
22:28:00.815 : EPR:3 1040 0.000 Z-probe bending correction B [mm]
22:28:00.831 : EPR:3 1044 0.000 Z-probe bending correction C [mm]
22:28:00.831 : EPR:0 880 1 Autolevel active (1/0)
22:28:00.831 : EPR:3 976 0.000000 tanXY Axis Compensation
22:28:00.831 : EPR:3 980 0.000000 tanYZ Axis Compensation
22:28:00.847 : EPR:3 984 0.000000 tanXZ Axis Compensation
22:28:00.847 : EPR:1 1048 55 Bed Preheat temp. [?C]
22:28:00.847 : EPR:0 106 0 Bed Heat Manager [0-3]
22:28:00.847 : EPR:0 107 255 Bed PID drive max
22:28:00.847 : EPR:0 124 80 Bed PID drive min
22:28:00.862 : EPR:3 108 196.000 Bed PID P-gain
22:28:00.862 : EPR:3 112 33.000 Bed PID I-gain
22:28:00.862 : EPR:3 116 290.000 Bed PID D-gain
22:28:00.862 : EPR:0 120 255 Bed PID max value [0-255]
22:28:00.862 : EPR:0 1020 0 Enable retraction conversion [0/1]
22:28:00.878 : EPR:3 992 3.000 Retraction length [mm]
22:28:00.878 : EPR:3 1000 40.000 Retraction speed [mm/s]
22:28:00.878 : EPR:3 1004 0.000 Retraction z-lift [mm]
22:28:00.878 : EPR:3 1008 0.000 Extra extrusion on undo retract [mm]
22:28:00.894 : EPR:3 1016 20.000 Retraction undo speed
22:28:00.894 : EPR:3 200 213.200 Extr.1 steps per mm
22:28:00.894 : EPR:3 204 50.000 Extr.1 max. feedrate [mm/s]
22:28:00.894 : EPR:3 208 20.000 Extr.1 start feedrate [mm/s]
22:28:00.894 : EPR:3 212 5000.000 Extr.1 acceleration [mm/s²]
22:28:00.909 : EPR:1 294 190 Extr.1 Preheat temp. [?C]
22:28:00.909 : EPR:0 216 3 Extr.1 heat manager [0-3]
22:28:00.909 : EPR:0 217 230 Extr.1 PID drive max
22:28:00.909 : EPR:0 245 40 Extr.1 PID drive min
22:28:00.909 : EPR:3 218 7.0000 Extr.1 PID P-gain/dead-time
22:28:00.925 : EPR:3 222 2.0000 Extr.1 PID I-gain
22:28:00.925 : EPR:3 226 40.0000 Extr.1 PID D-gain
22:28:00.925 : EPR:0 230 255 Extr.1 PID max value [0-255]
22:28:00.925 : EPR:2 231 0 Extr.1 X-offset [steps]
22:28:00.925 : EPR:2 235 0 Extr.1 Y-offset [steps]
22:28:00.940 : EPR:2 290 0 Extr.1 Z-offset [steps]
22:28:00.940 : EPR:1 239 1 Extr.1 temp. stabilize time [s]
22:28:00.940 : EPR:1 250 150 Extr.1 temp. for retraction when heating [C]
22:28:00.940 : EPR:1 252 0 Extr.1 distance to retract when heating [mm]
22:28:00.956 : EPR:0 254 255 Extr.1 extruder cooler speed [0-255]
22:28:00.956 : Echo:N1523 M205

Repetier

What does "The result is now that both on far left side(out of the rectangle) and right side (inside of the rectangle), the bed composition is totally ignored or not done at all. " mean? You can only reach position within 0-200 looking at the config.

Your bed leveling is now that great that you can disable G32 autoleveling at all. No need to move z on xy moves.

Zuru1

What I mean is that the print does not stick to either the left (x=0, 30) or right (x = 150, 200) side of the heated bed, but in between is ok.
After the calibration I thought that the issue of non sticking print to the bed would be resolved but that didn't help even if the bed was leveled.

Something is very weird with my printer, because before I manually leveled the bed it was the right side of the bed which was not sticking and now its both the left and right side of the bed.

Repetier

You should check if the bed is planar when hot. Some beds warp when hot resulting in different distances and if distance is too high sticking gets harder.

One typical trick is to print first layer with higher layer height and extrusion width.

Zuru1

The leveling was done with the bed and nozzle preheated for ABS and my first layer is height is 0.32mm on a 0.4 nozzle.
This is why I find this very strange since nothing that I do is helping to solve the issue.

Repetier

You missed "You should check if the bed is planar when hot.". Take a solid ruler and a light and put it on hot bed to see if bed is planar when hot. YOu see it best with light behind ruler then you see different intensity of light shining through. Autolevel assumes a planar bed and some hot beds bends so not being planar any more, hence the correction is not perfect. In that case you would add distortion correction to solve the bumps at lower z.