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Posted: **Sun Oct 23, 2016 10:21 pm**

I'm having trouble getting calibration results, the best I have been able to achieve is a 0.11 variance using the calculator at Escher3d.com. Some of my probe points are +0.15 to -0.16mm, while others are acceptable (~0.03 mm.)

I think part of the issue is the amount of play in the older V2 arms I have. See video here: https://youtu.be/d5xYvZ5dl0k
Will the injection molded carriages + ball/cup arms take this play out?

Out of curiousty, what kind of measurements does everyone else get when calibrating? I just installed FSR's on my bed to make it easier, but my results are similar to before.

Using 10 probe points at a max printable radius of 130mm, these are my latest results.

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Point   Coordinate          Measurement
0         X0 Y130            -0.07mm
1         X112.58 Y65        +0.15mm
2         X112.58 Y-65       -0.16mm
3         X0 Y-130           +0.15mm
4         X-112.58 Y-65      -0.12mm
5         X-112.58 Y65       +0.14mm
6         X0 Y65             -0.06mm
7         X56.29 Y-32.5      +0.04mm
8         X-56.29 Y-32.5     +0.03mm
9         X0 Y0              +0.04mm

Are these results normal? I saw another post where that user had within 0.02mm at probe points. I can't find that post now of course.
Belt tension seems fine, and the towers are not leaning in or out (checked with digital angle finder.)
Anything else I should check, or are the ball/cup arms the answer?

Posted: **Wed Oct 26, 2016 1:36 pm**

Any tips/thoughts suggestions?

Posted: **Sat Oct 29, 2016 1:42 am**

I played around with my physical endstop screws to get them all within 0.02mm of each other, and ran the calculator again.
So after numerous runs through the Escher 3D calculator, the best it can give me is a calculated 0.11mm deviation.
Using 6 factors and 10 points.
These are the results:
Endstop Corrections: X: 8 Y: 7 Z: 0
Diagonal Rod Length: 269.04
Delta Radius: 129.47
Homed Height 694.83
Tower Angle Corrections X: 0.36 Y: 0.4 Z: 0.00

Probing with 10 points results:
Point 0: -0.11mm
Point 1: +0.13mm
Point 2: -0.16mm
Point 3: +0.13mm
Point 4: -0.12mm
Point 5: +0.14mm
Point 6: -0.09mm
Point 7: +0.01mm
Point 8: +0.01mm
Point 9: +0.05mm

And Using Repetiers' bed height map tool I get this result:

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X:		 -90.00 -70.00 -50.00 -30.00 -10.00  10.00  30.00  50.00  70.00  90.00
y: 90.00	2.04	1.91	1.86	1.82	1.83	1.83	1.88	1.91	1.98	2.06
y: 70.00	1.98	1.92	1.86	1.87	1.86	1.87	1.91	1.93	1.98	2.03
y: 50.00	2.03	1.96	1.93	1.89	1.91	1.91	1.94	1.99	2.00	2.03
y: 30.00	2.01	1.99	1.98	1.97	1.96	1.98	2.01	2.03	2.02	2.04
y: 10.00	1.95	1.99	2.01	2.02	2.03	2.04	2.04	2.03	2.03	2.01
y:-10.00	1.94	1.97	2.02	2.03	2.07	2.04	2.04	2.03	2.01	1.93
y:-30.00	1.91	1.98	2.01	2.01	2.07	2.06	2.03	2.01	1.97	1.92
y:-50.00	1.88	1.97	2.02	2.04	2.08	2.08	2.04	2.02	1.97	1.91
y:-70.00	1.87	1.97	2.03	2.06	2.08	2.09	2.06	2.04	1.98	1.90
y:-90.00	1.86	1.96	2.03	2.08	2.11	2.13	2.09	2.05	1.96	1.85

These are my results after using Repetiers distortion correction:

Probing with 10 points results:
Point 0: +0.08mm
Point 1: +0.04mm
Point 2: -0.01mm
Point 3: -0.04mm
Point 4: -0.06mm
Point 5: +0.01mm
Point 6: -0.01mm
Point 7: -0.04mm
Point 8: -0.02mm
Point 9: -0.03mm

Bed height Measurements:

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X:		 -90.00 -70.00 -50.00 -30.00 -10.00  10.00  30.00  50.00  70.00  90.00
y:90.00 	1.99	1.99	2.00	2.01	1.99	1.99	1.97	1.98	1.95	1.99
y:70.00 	2.00	1.98	2.00	1.99	1.97	1.99	2.00	1.98	1.97	1.99
y:50.00 	2.00	1.99	1.99	1.98	1.98	1.99	2.00	1.98	1.97	1.99
y:30.00 	1.98	1.99	1.99	1.99	1.99	1.98	1.98	1.98	1.98	1.98
y:10.00 	1.98	1.99	1.98	1.98	1.97	1.98	1.98	1.98	1.99	1.97
y:-10.00	1.98	1.97	1.98	1.99	1.98	1.97	1.98	1.98	1.97	1.98
y:-30.00	1.99	1.99	1.99	1.98	1.98	1.97	1.98	1.98	1.96	1.98
y:-50.00	1.98	1.97	1.97	1.98	1.98	1.98	1.98	1.97	1.98	1.97
y:-70.00	1.98	1.98	1.98	1.98	1.99	1.99	1.97	1.97	1.97	1.96
y:-90.00	1.99	1.98	1.97	1.98	1.98	1.99	1.99	1.99	1.99	1.98

The only thing I am hesitant to use the distortion correction because this only corrects the first layer. And it doesn't really appear to do much looking at the 10 point probe.
Is there any other way to improve my calibration results?
Any input is appreciated.
I can print small (<100 mm diameter) objects fine, but anything larger and the difference in height comes into play and causes first layer adhesion problems.

Posted: **Sat Oct 29, 2016 7:39 am**

The play I see in your video is not different then I am experiencing. I havent tried so many probe points though. 3 point calibration at the towers (endstop correction and center) I can get to 0.02, but if I probe in between towers I get sometimes 0.10. I can see my effector tilting a bit though when the hotend tips the bed while probing (fsr setup). And also I think braided sleeve I use is way too stiff... It is one with Velcro thatvyou can wrap around the cabling. It seems to jerk the hotend while moving. I ordered an other type to replace it.

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