Ok Russ just got this off the Google forum try {G30 A Dnnn} for auto cal.

On Tuesday, 2 December 2014 15:23:43 UTC-4, Haydn Huntley wrote:

BTW, I have a slightly different opinion on using RC's Marlin for making a delta printer print well.

I've used it on two different printers, with a variety of beds, arms, and hotends on each printer, so I've done it successfully more than 10 times.

If you just try to use "G30 A", it doesn't do a very good job. For some reason it seems to have a hard time inferring the horizontal radius and diagonal rod length, even when you start it off with the right values. I have been able to get calibrations like this, but they tended to print parts which were either too large or too small by a few percent.

I also bought a 30cm micrometer and used it to precisely measure my diagonal rods (I've been building carbon fiber ones with zero-backlash magnetic joints), so then I could use the "G30 A Dnnn" command, which calibrated within less than 10 iterations, and did an excellent job.

Neal wrote:

I just tried this and you were right, it completed in only 7 iterations, but it doesn't do any compensation for the tower radius errors. They were slightly off when I ran the full G30 A as you can see below. Will this have a dramatic effect on my final prints? Can I use the values that I got from the full G30A or will that throw off the other variables?

G30 A result:

M666 X-2.45 Y-1.65 Z-2.70

M666 A-0.21 B0.55 C-0.34 E-0.88 F0.00 G0.31 R123.00 D206.00 H284.40 P0.00

G30 D198.6 A result:

M666 X-2.75 Y-1.35 Z-2.05

M666 A0.00 B0.00 C0.00 E0.00 F0.00 G0.00 R121.20 D198.60 H284.62 P0.00

Haydn Huntley wrote:

@Neil, When I did it on mine, it did calculate values for ABC and IJK, though they were small.

You should look at the numbers on the left side of your printouts, which showed how close everything was to zero (tram).

On mine, the worst error was 0.110mm, which is 110 microns, which is good enough for me. I print layers which are 200 microns.

Here is what I got:

>>>G30 A D287.91

SENDING:G30 A D287.91

Starting Auto Calibration..

Z-Tower Endstop Offsets

-12.1250 X:0.00 Y:0.00 Z:0.00

-12.3300 -12.2300 Tower Position Adjust

-12.2450 A:0.00 B:0.00 C:0.00

-12.1950 -12.1900 I:0.00 J:0.00 K:0.00

-12.1100 Delta Radius: 160.0000

X-Tower Y-Tower Diag Rod: 287.9100

Using diagional rod length: 287.91mm (will not be adjusted)

Iteration: 1

Adjusting Z-Height to: 293.25 mm..

.

.

.

Iteration: 7

Adjusting Endstops..

Z-Tower Endstop Offsets

-0.0050 X:-2.07 Y:-2.12 Z:-1.80

-0.1100 -0.1000 Tower Position Adjust

-0.0000 A:0.22 B:-0.16 C:-0.06

-0.0050 -0.0150 I:0.00 J:0.00 K:0.00

0.0300 Delta Radius: 160.5000

X-Tower Y-Tower Diag Rod: 287.9100

Auto Calibration Complete

Issue M500 Command to save calibration settings to EPROM (if enabled)

I believe the "G30 E" command will probe and show the results. The following is what I started with:

>>>G30 E

SENDING:G30 E

Z-Tower Endstop Offsets

1.5000 X:0.00 Y:0.00 Z:0.00

1.2550 1.1900 Tower Position Adjust

2.0150 A:0.00 B:0.00 C:0.00

1.4050 1.5350 I:0.00 J:0.00 K:0.00

1.5150 Delta Radius: 160.0000

X-Tower Y-Tower Diag Rod: 287.9100

*:cool:**:D**:D*On Tuesday, 2 December 2014 15:23:43 UTC-4, Haydn Huntley wrote:

BTW, I have a slightly different opinion on using RC's Marlin for making a delta printer print well.

I've used it on two different printers, with a variety of beds, arms, and hotends on each printer, so I've done it successfully more than 10 times.

If you just try to use "G30 A", it doesn't do a very good job. For some reason it seems to have a hard time inferring the horizontal radius and diagonal rod length, even when you start it off with the right values. I have been able to get calibrations like this, but they tended to print parts which were either too large or too small by a few percent.

I also bought a 30cm micrometer and used it to precisely measure my diagonal rods (I've been building carbon fiber ones with zero-backlash magnetic joints), so then I could use the "G30 A Dnnn" command, which calibrated within less than 10 iterations, and did an excellent job.

Neal wrote:

I just tried this and you were right, it completed in only 7 iterations, but it doesn't do any compensation for the tower radius errors. They were slightly off when I ran the full G30 A as you can see below. Will this have a dramatic effect on my final prints? Can I use the values that I got from the full G30A or will that throw off the other variables?

G30 A result:

M666 X-2.45 Y-1.65 Z-2.70

M666 A-0.21 B0.55 C-0.34 E-0.88 F0.00 G0.31 R123.00 D206.00 H284.40 P0.00

G30 D198.6 A result:

M666 X-2.75 Y-1.35 Z-2.05

M666 A0.00 B0.00 C0.00 E0.00 F0.00 G0.00 R121.20 D198.60 H284.62 P0.00

Haydn Huntley wrote:

@Neil, When I did it on mine, it did calculate values for ABC and IJK, though they were small.

You should look at the numbers on the left side of your printouts, which showed how close everything was to zero (tram).

On mine, the worst error was 0.110mm, which is 110 microns, which is good enough for me. I print layers which are 200 microns.

Here is what I got:

>>>G30 A D287.91

SENDING:G30 A D287.91

Starting Auto Calibration..

Z-Tower Endstop Offsets

-12.1250 X:0.00 Y:0.00 Z:0.00

-12.3300 -12.2300 Tower Position Adjust

-12.2450 A:0.00 B:0.00 C:0.00

-12.1950 -12.1900 I:0.00 J:0.00 K:0.00

-12.1100 Delta Radius: 160.0000

X-Tower Y-Tower Diag Rod: 287.9100

Using diagional rod length: 287.91mm (will not be adjusted)

Iteration: 1

Adjusting Z-Height to: 293.25 mm..

.

.

.

Iteration: 7

Adjusting Endstops..

Z-Tower Endstop Offsets

-0.0050 X:-2.07 Y:-2.12 Z:-1.80

-0.1100 -0.1000 Tower Position Adjust

-0.0000 A:0.22 B:-0.16 C:-0.06

-0.0050 -0.0150 I:0.00 J:0.00 K:0.00

0.0300 Delta Radius: 160.5000

X-Tower Y-Tower Diag Rod: 287.9100

Auto Calibration Complete

Issue M500 Command to save calibration settings to EPROM (if enabled)

I believe the "G30 E" command will probe and show the results. The following is what I started with:

>>>G30 E

SENDING:G30 E

Z-Tower Endstop Offsets

1.5000 X:0.00 Y:0.00 Z:0.00

1.2550 1.1900 Tower Position Adjust

2.0150 A:0.00 B:0.00 C:0.00

1.4050 1.5350 I:0.00 J:0.00 K:0.00

1.5150 Delta Radius: 160.0000

X-Tower Y-Tower Diag Rod: 287.9100