Print bed level calibration of Mini Kossel using M666

A is center of the print bed. B is tower X, C is tower Y, D is tower Z.

Manual calibration of print level makes the nozzle moving across one plane.

The calibration step is followed by.

Step 1: Set Z height at the center of bed. In this example, previous Z height was 215.70 mm where the nozzle touches the test paper whose thickness around 0.1 mm in middle of print bed. People use A4 or letter size print paper.  Use M114 to find current coordinate of the nozzle. The nozzle moved -1.65 mm below the Z height. So I increased the Z height by commensing  M666 H217.35.

New Z height = old Z height – difference

New Z height = 215.70 – (-1.65) = 217.35 mm

print_bed_leveling_howto_1

print_bed_leveling_howto_2

print_bed_leveling_howto_3

03/28/2015

Hopefully I gonna start printing object again within a day.

cDSC_0017

Three points base
cDSC_0018

I manually sanded the aluminium print bed, drilled three holes on the bottom side for precision level adjustment. When I inspected the top surface using a filler gauge whose minimum gap blade is 0.04 mm and a engineering square, I couldn’t find any high or lower spot that takes the blade.

However half hour of manual level calibration followed by G29 Auto level probe data showed about 0.2 mm level difference across the bed surface. I see there was huge improvement of print bed. At this point I’m skeptical about accuracy of the Auto level probe.

cDSC_0015

>>> M666 L
SENDING:M666 L
Current Delta geometry values:
X (Endstop Adj): -5.40
Y (Endstop Adj): -5.05
Z (Endstop Adj): -4.95
P (Z-Probe Offset): X10.95 Y-4.30 Z-5.80
A (Tower A Position Correction): 0.00
B (Tower B Position Correction): 0.00
C (Tower C Position Correction): 0.00
I (Tower A Radius Correction): 0.00
J (Tower B Radius Correction): 0.00
K (Tower C Radius Correction): 0.00
R (Delta Radius): 111.50
D (Diagonal Rod Length): 214.86
H (Z-Height): 211.60

print_bed_level_0328_1

20.00,60.00, -0.290
0.00,60.00, -0.270
-20.00, 60.00, -0.330
-40.00, 40.00, -0.150
-20.00, 40.00, -0.180
0.00, 40.00, -0.170
20.00, 40.00, -0.170
40.00, 40.00, 0.040
60.00, 20.00, 0.020
40.00, 20.00, -0.020
20.00, 20.00, -0.050
0.00, 20.00,-0.080
-20.00, 20.00, -0.140
-40.00, 20.00, -0.170
-60.00, 20.00, 0.150
-60.00, 0.00, 0.110
-40.00, 0.00, 0.060
-20.00, 0.00, -0.020
0.00, 0.00, -0.090
20.00, 0.00, -0.150
40.00, 0.00, -0.170
60.00, 0.00, 0.330
60.00, -20.00, 0.260
40.00, -20.00, 0.200
20.00, -20.00, 0.120
0.00, -20.00, 0.020
-20.00, -20.00, -0.050
-40.00, -20.00, -0.150
-60.00, -20.00, 0.300
-40.00, -40.00, 0.210
-20.00, -40.00, 0.150
0.00, -40.00, 0.040
20.00, -40.00, -0.070
40.00, -40.00, 0.260
20.00, -60.00, 0.260
0.00, -60.00, 0.210
-20.00, -60.00, 0.110

print_bed_level_0328_2


20.00,60.00, -0.260
0.00,60.00, -0.250
-20.00, 60.00, -0.280
-40.00, 40.00, -0.080
-20.00, 40.00, -0.090
0.00, 40.00, -0.120
20.00, 40.00, -0.140
40.00, 40.00, -0.160
60.00, 20.00, 0.090
40.00, 20.00, 0.070
20.00, 20.00, 0.020
0.00, 20.00,-0.020
-20.00, 20.00, -0.070
-40.00, 20.00, -0.130
-60.00, 20.00, -0.160
-60.00, 0.00, 0.200
-40.00, 0.00, 0.190
-20.00, 0.00, 0.100
0.00, 0.00, 0.020
20.00, 0.00, -0.050
40.00, 0.00, -0.120
60.00, 0.00, 0.150
60.00, -20.00, 0.210
40.00, -20.00, 0.140
20.00, -20.00, 0.120
0.00, -20.00, 0.050
-20.00, -20.00, -0.030
-40.00, -20.00, -0.070
-60.00, -20.00, 0.150
-40.00, -40.00, 0.180
-20.00, -40.00, 0.110
0.00, -40.00, 0.030
20.00, -40.00, -0.090
40.00, -40.00, 0.270
20.00, -60.00, 0.270
0.00, -60.00, 0.220
-20.00, -60.00, 0.130

3/31/2015

The Auto calibration indeed worked out this time.
It turned out hard-to-find calibration bug was loose pulley of X axis’ stepper motor. The pulley supposedly secured by two M3 set scews but one set screw was barely holding it. The pulley was 5 mm to 10 mm off from the original position on the shaft.

SENDING:M666 L
Current Delta geometry values:
X (Endstop Adj): -4.68
Y (Endstop Adj): -4.23
Z (Endstop Adj): -4.65
P (Z-Probe Offset): X10.95 Y-4.30 Z-5.80
A (Tower A Position Correction): 0.00
B (Tower B Position Correction): 0.00
C (Tower C Position Correction): 0.00
I (Tower A Radius Correction): 0.00
J (Tower B Radius Correction): 0.00
K (Tower C Radius Correction): 0.00
R (Delta Radius): 110.95
D (Diagonal Rod Length): 213.25
H (Z-Height): 207.05
>>> g30 A D213.25
SENDING:G30 A D213.25
Starting Auto Calibration..
Z-Tower Endstop Offsets
-0.3500 X:-4.68 Y:-4.23 Z:-4.65
-0.2700 -0.3400 Tower Position Adjust
-0.1800 A:0.00 B:0.00 C:0.00
0.0600 -0.5200 I:0.00 J:0.00 K:0.00
-0.1700 Delta Radius: 110.9500
X-Tower Y-Tower Diag Rod: 213.2500
Using diagional rod length: 213.25mm (will not be adjusted)
Iteration: 1
Adjusting Endstops..
Z-Tower Endstop Offsets
-0.0200 X:-4.62 Y:-4.73 Z:-4.98
-0.1100 0.1100 Tower Position Adjust
0.0500 A:0.00 B:0.00 C:0.00
0.0900 -0.0900 I:0.00 J:0.00 K:0.00
0.0100 Delta Radius: 110.9500
X-Tower Y-Tower Diag Rod: 213.2500
Iteration: 2
Adjusting Endstops..
Z-Tower Endstop Offsets
0.0100 X:-4.54 Y:-4.81 Z:-5.00
-0.1400 0.1300 Tower Position Adjust
0.0600 A:0.00 B:0.00 C:0.00
0.0100 -0.0500 I:0.00 J:0.00 K:0.00
-0.0000 Delta Radius: 110.9500
X-Tower Y-Tower Diag Rod: 213.2500
Iteration: 3
Adjusting Endstops..
Z-Tower Endstop Offsets
-0.0300 X:-4.53 Y:-4.86 Z:-4.99
-0.1800 0.1600 Tower Position Adjust
0.0400 A:0.00 B:0.00 C:0.00
-0.0000 -0.0100 I:0.00 J:0.00 K:0.00
0.0100 Delta Radius: 110.9500
X-Tower Y-Tower Diag Rod: 213.2500
Iteration: 4
Adjusting Endstops..
Z-Tower Endstop Offsets
0.0100 X:-4.53 Y:-4.87 Z:-5.02
-0.1500 0.2000 Tower Position Adjust
0.0500 A:0.00 B:0.00 C:0.00
-0.0100 0.0100 I:0.00 J:0.00 K:0.00
0.0100 Delta Radius: 110.9500
X-Tower Y-Tower Diag Rod: 213.2500
Iteration: 5
Endstops: OK
Adjusting Delta Geometry..
Adjusting Delta Radius (110.95 -> 109.95)
Z-Tower Endstop Offsets
-0.2800 X:-4.53 Y:-4.87 Z:-5.02
-0.3700 -0.1800 Tower Position Adjust
-0.5400 A:0.00 B:0.00 C:0.00
-0.2700 -0.3900 I:0.00 J:0.00 K:0.00
-0.3300 Delta Radius: 109.9500
X-Tower Y-Tower Diag Rod: 213.2500
equalAB=false
equalBC=false
equalCA=false
c: -0.54 x: -0.27 y: -0.39 z: -0.28 ox: -0.18 oy: -0.37 oz: -0.33
radius:109.9500 diagrod:213.2500
Radius Adj Complete: No DiagRod Adj Complete: Yes
RadiusA Error: -0.09 (adjust: 0.00)
RadiusB Error: -0.02 (adjust: 0.00)
RadiusC Error: 0.05 (adjust: 0.00)
DeltaAlphaA: -0.04
DeltaAlphaB: -0.15
DeltaAlphaC: 0.19
Adjusting Delta Radius (109.95 -> 110.45)
Z-Tower Endstop Offsets
-0.1300 X:-4.53 Y:-4.87 Z:-5.02
-0.1700 -0.1200 Tower Position Adjust
-0.2300 A:0.04 B:0.15 C:-0.19
-0.1100 -0.2300 I:0.00 J:0.00 K:0.00
-0.1500 Delta Radius: 110.4500
X-Tower Y-Tower Diag Rod: 213.2500
equalAB=false
equalBC=false
Tower CA Equal (C=0.02 A=0.01)
TowerB Radius error - adjusting
adj_RadiusB set to 0.50
c: -0.23 x: -0.11 y: -0.23 z: -0.13 ox: -0.12 oy: -0.17 oz: -0.15
radius:110.4500 diagrod:213.2500
Radius Adj Complete: No DiagRod Adj Complete: Yes
RadiusA Error: 0.01 (adjust: 0.00)
RadiusB Error: -0.06 (adjust: 0.50)
RadiusC Error: 0.02 (adjust: 0.00)
DeltaAlphaA: -0.02
DeltaAlphaB: -0.03
DeltaAlphaC: 0.05
Adjusting Delta Radius (110.45 -> 110.95)
Z-Tower Endstop Offsets
0.0300 X:-4.53 Y:-4.87 Z:-5.02
-0.1400 0.1400 Tower Position Adjust
0.1400 A:0.06 B:0.18 C:-0.24
0.0300 0.0800 I:0.00 J:0.50 K:0.00
0.1400 Delta Radius: 110.9500
X-Tower Y-Tower Diag Rod: 213.2500
equalAB=false
equalBC=false
Tower CA Equal (C=-0.11 A=-0.11)
TowerB Radius error - adjusting
c: 0.14 x: 0.03 y: 0.08 z: 0.03 ox: 0.14 oy: -0.14 oz: 0.14
radius:110.9500 diagrod:213.2500
Radius Adj Complete: No DiagRod Adj Complete: Yes
RadiusA Error: -0.11 (adjust: 0.00)
RadiusB Error: 0.22 (adjust: -0.25)
RadiusC Error: -0.11 (adjust: 0.00)
DeltaAlphaA: -0.28
Adjusting Delta Radius (110.95 -> 110.70)
Z-Tower Endstop Offsets
0.0200 X:-4.53 Y:-4.87 Z:-5.02
0.0800 -0.0700 Tower Position Adjust
-0.0300 A:0.34 B:0.18 C:-0.52
0.0100 -0.0900 I:0.00 J:0.25 K:0.00
-0.0700 Delta Radius: 110.7000
X-Tower Y-Tower Diag Rod: 213.2500
equalAB=false
equalBC=false
Tower CA Equal (C=0.09 A=0.08)
TowerB Radius error - adjusting
c: -0.03 x: 0.01 y: -0.09 z: 0.02 ox: -0.07 oy: 0.08 oz: -0.07
radius:110.7000 diagrod:213.2500
Radius Adj Complete: Yes DiagRod Adj Complete: Yes
RadiusA Error: 0.08 (adjust: 0.00)
RadiusB Error: -0.17 (adjust: 0.12)
RadiusC Error: 0.09 (adjust: 0.00)
DeltaAlphaA: 0.15
DeltaAlphaB: 0.00
DeltaAlphaC: -0.15
Z-Tower Endstop Offsets
0.2000 X:-4.53 Y:-4.87 Z:-5.02
0.2900 0.0200 Tower Position Adjust
0.1400 A:0.34 B:0.18 C:-0.52
0.2000 -0.0600 I:0.00 J:0.25 K:0.00
0.0300 Delta Radius: 110.7000
X-Tower Y-Tower Diag Rod: 213.2500
Iteration: 6
Adjusting Endstops..
Z-Tower Endstop Offsets
0.0200 X:-4.34 Y:-4.93 Z:-4.83
0.0900 -0.0400 Tower Position Adjust
0.0100 A:0.34 B:0.18 C:-0.52
0.0200 -0.0400 I:0.00 J:0.25 K:0.00
-0.0400 Delta Radius: 110.7000
X-Tower Y-Tower Diag Rod: 213.2500
Iteration: 7
Adjusting Endstops..
Z-Tower Endstop Offsets
0.0100 X:-4.32 Y:-4.96 Z:-4.81
0.0700 -0.0400 Tower Position Adjust
0.0100 A:0.34 B:0.18 C:-0.52
0.0200 -0.0200 I:0.00 J:0.25 K:0.00
-0.0400 Delta Radius: 110.7000
X-Tower Y-Tower Diag Rod: 213.2500
Auto Calibration Complete
Issue M500 Command to save calibration settings to EPROM (if enabled)
>>> M500
SENDING:M500
echo:Settings Stored
SENDING:M666 L
Current Delta geometry values:
X (Endstop Adj): -4.32
Y (Endstop Adj): -4.96
Z (Endstop Adj): -4.81
P (Z-Probe Offset): X10.95 Y-4.30 Z-5.80
A (Tower A Position Correction): 0.34
B (Tower B Position Correction): 0.18
C (Tower C Position Correction): -0.52
I (Tower A Radius Correction): 0.00
J (Tower B Radius Correction): 0.25
K (Tower C Radius Correction): 0.00
R (Delta Radius): 110.70
D (Diagonal Rod Length): 213.25
H (Z-Height): 207.05
>>> g29
SENDING:G29
0.020 0.020 0.020 0.030 0.020 0.020 0.020
0.050 0.050 0.030 0.020 0.020 -0.010 -0.010
0.100 0.070 0.050 0.020 -0.010 -0.020 -0.040
0.080 0.050 0.030 0.000 -0.010 -0.030 -0.050
0.060 0.020 0.000 -0.020 -0.030 -0.030 -0.050
-0.020 -0.020 -0.040 -0.030 -0.010 -0.010 -0.010
-0.050 -0.050 -0.050 -0.030 0.020 0.020 0.020

>>> g30 x-20 y-60
SENDING:G30 X-20 Y-60
Bed Z-Height at X:-20.00 Y:-60.00 = -0.0500
Carriage Positions: [208.98, 176.90, 135.24]

20.00,60.00, 0.020
0.00,60.00, 0.010
-20.00, 60.00, -0.000
-40.00, 40.00, 0.040
-20.00, 40.00, 0.030
0.00, 40.00, 0.020
20.00, 40.00, 0.020
40.00, 40.00, -0.010
60.00, 20.00, -0.040
40.00, 20.00, -0.020
20.00, 20.00, -0.010
0.00, 20.00, 0.020
-20.00, 20.00, 0.050
-40.00, 20.00, 0.070
-60.00, 20.00,0.100
-60.00, 0.00, 0.100
-40.00, 0.00, 0.060
-20.00, 0.00, 0.030
0.00, 0.00, -0.000
20.00, 0.00, -0.020
40.00, 0.00, -0.030
60.00, 0.00,-0.050
60.00, -20.00, -0.050
40.00, -20.00, -0.030
20.00, -20.00, -0.030
0.00, -20.00, -0.020
-20.00, -20.00, 0.010
-40.00, -20.00, 0.030
-60.00, -20.00,0.080
-40.00, -40.00, -0.010
-20.00, -40.00, -0.030
0.00, -40.00, -0.030
20.00, -40.00, -0.010
40.00, -40.00, -0.000
20.00, -60.00, 0.020
0.00, -60.00, -0.030
-20.00, -60.00, -0.050

lp_03312015_final

delta_parmeter_fit

About janpenguin

Email: janpenguin [at] riseup [dot] net Every content on the blog is made by Free and Open Source Software in GNU/Linux.
This entry was posted in Reprap 3D Printer and tagged , , , , , , , . Bookmark the permalink.

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