Auto bed leveling constantly diffrent

I have build a new printer with the spec below but it won't auto level properly. The Z screw moves on the first layer but its like it's doing it in reverse to what it needs too. I have checked and checked and I can't seem to find anything wrong. Below is the spec and the starting gcode any help would be greatly received. I have even done the steps for the Z motor and that was only out by 8 over 400. BlTouch I coming back with different numbers when probed.


BTT SKR PRO V1.2
TMC2209 V3.1 UART. leg removed on X,Y,Z but not on E0,E1,E2
BTT TFT35
BlTouch 3.1
THC-01 hotend

Start Gcode:

G92 E0 ; Reset Extruder
G92 E1 ; Reset Extruder
G92 E2 ; Reset Extruder
G28 ; Home all axes
G29 ; Bedlevel
M500 ; EEPROM Save
G1 Z2.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed
G1 X0.1 Y20 Z0.3 F5000.0 ; Move to start position
G1 X0.1 Y200.0 Z0.3 F1500.0 E15 ; Draw the first line
G1 X0.4 Y200.0 Z0.3 F5000.0 ; Move to side a little
G1 X0.4 Y20 Z0.3 F1500.0 E30 ; Draw the second line
G92 E0 ; Reset Extruder
G92 E1 ; Reset Extruder
G92 E2 ; Reset Extruder
G1 Z2.0 F3000 ; Move Z Axis up little to prevent scratching of Heat Bed
G1 X5 Y20 Z0.3 F5000.0 ; Move over to prevent blob squish

Edited 2 time(s). Last edit at 03/20/2021 03:45PM by Bossydale.

Results from 4 bed levels in a row with a 5x5 probe on the bed. nothing was changed between probes same temp and untouched. I have changed the wheels for the bed and hotend just incase but it hasn't changed anything. I've cleaned the bltouch with no change. Now i gonna give UBL a go and see if that does anything to help.


Recv: 0 1 2 3 4
Recv: 0 -0.013 -0.182 -0.315 -0.530 -0.802
Recv: 1 +0.465 +0.288 +0.072 -0.190 -0.517
Recv: 2 +0.810 +0.652 +0.480 +0.220 -0.072
Recv: 3 +1.253 +1.082 +0.855 +0.565 +0.215
Recv: 4 +1.515 +1.375 +1.230 +0.990 +0.690

Recv: 0 1 2 3 4
Recv: 0 +0.007 -0.152 -0.287 -0.513 -0.785
Recv: 1 +0.465 +0.295 +0.060 -0.200 -0.523
Recv: 2 +0.828 +0.693 +0.520 +0.277 +0.000
Recv: 3 +1.410 +1.257 +1.043 +0.665 +0.295
Recv: 4 +1.670 +1.523 +1.372 +1.130 +0.818

Recv: 0 1 2 3 4
Recv: 0 +0.263 +0.138 -0.130 -0.243 -0.487
Recv: 1 +0.538 +0.400 +0.187 -0.060 -0.357
Recv: 2 +0.787 +0.638 +0.473 +0.237 -0.017
Recv: 3 +1.350 +1.205 +0.735 +0.460 +0.150
Recv: 4 +1.490 +1.392 +1.260 +1.197 +0.945

Recv: 0 1 2 3 4
Recv: 0 +0.163 +0.035 -0.070 -0.260 -0.500
Recv: 1 +0.520 +0.398 +0.193 -0.057 -0.357
Recv: 2 +0.727 +0.618 +0.460 +0.247 +0.007
Recv: 3 +0.997 +0.898 +0.717 +0.467 +0.178
Recv: 4 +1.112 +1.007 +0.865 +0.655 +0.405

UBL results. I'm going to try a new probe and use manual bed leveling for the minute as I have a glass bed so it shouldn't be to hard to sort

199 NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN
177 NaN 1.665 1.403 1.175 1.072 1.225 1.285 1.155 NaN NaN
155 NaN 1.308 1.062 0.852 0.820 0.890 1.115 1.120 NaN NaN
133 NaN 0.980 0.572 0.460 0.338 0.588 0.755 1.000 NaN NaN
111 NaN 0.723 0.475 0.300 0.250 0.322 0.515 0.815 NaN NaN
89 NaN 0.572 0.338 0.200 0.118 0.273 0.477 0.835 NaN NaN
67 NaN 0.658 0.322 0.150 0.092 0.253 0.428 0.800 NaN NaN
45 NaN 0.757 0.470 0.308 0.237 0.240 0.423 0.783 NaN NaN
23 NaN 1.088 0.730 0.435 0.505 0.505 0.882 0.798 NaN NaN
1 NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN
1 26 52 77 102 128 153 178 204 229

199 NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN
177 NaN 1.742 1.613 1.385 1.290 1.358 1.552 1.430 NaN NaN
155 NaN 1.485 1.148 0.930 0.905 1.078 1.263 1.382 NaN NaN
133 NaN 1.050 0.638 0.513 0.398 0.670 0.995 1.243 NaN NaN
111 NaN 0.763 0.487 0.310 0.273 0.390 0.670 0.977 NaN NaN
89 NaN 0.640 0.372 0.233 0.155 0.332 0.612 1.007 NaN NaN
67 NaN 0.730 0.362 0.195 0.138 0.332 0.600 0.985 NaN NaN
45 NaN 0.815 0.515 0.372 0.295 0.312 0.615 1.015 NaN NaN
23 NaN 1.305 0.828 0.497 0.608 0.655 1.090 1.070 NaN NaN
1 NaN NaN NaN NaN NaN NaN NaN NaN NaN NaN
1 26 52 77 102 128 153 178 204 229

Still no change. I've ordered linear rails and a new BLTouch hope this works. Will post outcome

I have fitted the linear rails and dual z. This seems to of sorted the problem for now and made a new lol. Onwards and upwards lol