G29 autolevelling destruction G2S

[moriartynz]

Hi All,

Anyone got any advice concerning autolevelling using the G29 command?

When I issue the G29 command, it does a series of probe points that show a variance of up to 3mm in the Z axis. Directly AFTER developing the autolevelling probing matrix, the head tries to move up and outside of the printable area somewhere in the X and Y negative territory, putting strain on the carriages, requiring an emergency stop in Repetier.

It seems that some command in the firmware is either miscalibrating positions after autolevelling or the G29 ends with a repositioning step that is not appropriate for the G2S.

Before doing a G29, I have my system set up so that I can issue G0 commands (e.g. G0 X0 Y0 Z0), which moves the head down and touches the head to the tape on the bed. I can also move the head around the bed to different points, so that it good.

I look forward to hearing from you.

Regards
Mark

[Mark]

Have you checked your endstop? Are they working well?

[moriartynz]

Hello Mark,

Thanks for getting back to me. Yes, all endstops are working well. I have confirmed their statuses using the M119 command. I have also done this separately while homed and elsewhere to check that these statuses change. I have also done the M119 and checked the status changes when the probe is down and when the probe is up. As I said, there appears to be a problem with the firmware somewhere after getting the probing matrix and before the end of the G29 command.

[Mark]

How about your Z axis height? did you difine it ? Or the Z probe offset ?

[rickr]

Did you find a resolution to this issue? I have the same problem, but instead of destroying the printer I have put together a small scenario which demonstrates the problem and I have uploaded a video to youtube to see it happening. As the audio didn't come out too well I have created this description to help you, https://youtu.be/mLSMqfLYiY8

This video demonstrates resetting the above printer, connecting to it with repetier, select moving the Z axis by 1mm and then the printer moves the Z location without stopping and in the wrong direction (fixable). However it doesn't stop until I press the emergency stop. Unfortunately the audio is not very good on the video so you can't hear the extruders being banged into the hotbed until I stop it.

Then to make things worse, even though the Z-axis end stop is released (activated) the motor movement did not stop.

Regards, Rick

[moriartynz]

Hi Mark,

Yes, these things are all measured and defined. I attach my configuration file.

Here is the output from the various M119 tests and the G29:
M119 when homed (probe down):
12:29:42.597 : Reporting endstop status
12:29:42.597 : x_max: TRIGGERED
12:29:42.597 : y_max: TRIGGERED
12:29:42.597 : z_min: open
12:29:42.597 : z_max: TRIGGERED

M119 when homed (probe up):
12:31:38.344 : Reporting endstop status
12:31:38.344 : x_max: TRIGGERED
12:31:38.344 : y_max: TRIGGERED
12:31:38.344 : z_min: TRIGGERED
12:31:38.344 : z_max: TRIGGERED

G0 X0 Y0 Z1
M119 (probe down)
12:33:11.618 : Reporting endstop status
12:33:11.618 : x_max: open
12:33:11.618 : y_max: open
12:33:11.618 : z_min: open
12:33:11.618 : z_max: open

G0 X0 Y0 Z0
M119 (probe down)
12:34:18.883 : Reporting endstop status
12:34:18.883 : x_max: open
12:34:18.883 : y_max: open
12:34:18.883 : z_min: TRIGGERED
12:34:18.883 : z_max: open

Home
G29 (probe down)
Output (emergency stop at the end when the head moves outside of print area and tries to destroy itself):
12:36:12.034 : Bed x: 31.50 y: -31.50 z: 1.53
12:36:16.011 : Bed x: 15.75 y: -31.50 z: 0.39
12:36:19.636 : Bed x: 0.00 y: -31.50 z: 0.30
12:36:23.150 : Bed x: -15.75 y: -31.50 z: 0.43
12:36:26.695 : Bed x: -31.50 y: -31.50 z: 0.43
12:36:30.177 : Bed x: -31.50 y: -15.75 z: 0.96
12:36:33.723 : Bed x: -15.75 y: -15.75 z: 1.05
12:36:37.268 : Bed x: 0.00 y: -15.75 z: 1.11
12:36:40.925 : Bed x: 15.75 y: -15.75 z: 0.98
12:36:44.535 : Bed x: 31.50 y: -15.75 z: 1.60
12:36:48.049 : Bed x: 31.50 y: 0.00 z: 1.99
12:36:52.026 : Bed x: 15.75 y: 0.00 z: 1.04
12:36:55.636 : Bed x: 0.00 y: 0.00 z: 1.20
12:36:59.196 : Bed x: -15.75 y: 0.00 z: 1.30
12:37:02.774 : Bed x: -31.50 y: 0.00 z: 1.29
12:37:06.240 : Bed x: -31.50 y: 15.75 z: 1.81
12:37:09.849 : Bed x: -15.75 y: 15.75 z: 1.75
12:37:13.442 : Bed x: 0.00 y: 15.75 z: 1.76
12:37:17.147 : Bed x: 15.75 y: 15.75 z: 1.64
12:37:20.804 : Bed x: 31.50 y: 15.75 z: 2.50
12:37:24.334 : Bed x: 31.50 y: 31.50 z: 3.43
12:37:28.550 : Bed x: 15.75 y: 31.50 z: 2.01
12:37:32.272 : Bed x: 0.00 y: 31.50 z: 2.09
12:37:35.929 : Bed x: -15.75 y: 31.50 z: 1.99
12:37:39.571 : Bed x: -31.50 y: 31.50 z: 1.94
12:37:39.593 : -0.67 -0.67 -0.80 -0.71 0.43
12:37:39.593 : -0.14 -0.05 0.01 -0.12 0.50
12:37:39.594 : 0.19 0.20 0.10 -0.06 0.89
12:37:39.594 : 0.71 0.65 0.66 0.54 1.40
12:37:39.594 : 0.84 0.89 0.99 0.91 2.33
12:37:42.728 : start
12:37:42.728 : echo: External Reset

Thanks for your assistance.
Regards
Mark

[Mark]

I'm trying to figure this out ,plz give me some time and be patient , thank you!

[moriartynz]

Hi Rickr,

I found that the configuration file needed to be changed to account for the way the stops were set up.

This might be a case of the blind leading the blind, but test something for me please. I assume that HOME ends up with the carriages at the top of your frame (not heading to the bed). Let me know if that is not the case.

Set your machine so the head is floating in the air and put the probe into the testing position (poking down). Do a M119 command. Also, please put the probe into the stored position (up), home your device (click home button), do a M119 and post the output results for both of these M119 commands.

If your microswitches are working and your device is homing correctly, then the first M119 output will have exactly an inverted result of the second M119 result. If not then it is likely that one or more of the switches are not connected properly or not being actuated by the carriages in the home position.

This should also tell us what the state of your microswitches are in for the various positions. I found that the output from the microswitches vary depending on the microswitch and the terminals that the wires are connected to. These have to be correctly identified in the Merlin firmware confuguration file in Arduino IDE.

Condolences in common misery
Mark

[rickr]

Hi Mark, thanks again for your help.

Home is at the hotbed and based on what it is doing, home is probably somewhere near my shoes

When I send the M119, nothing happens. For the sake of finding out what actually happens now when I issue the G29 command it shoots off the hotbed (the probe ends up over the edge of the hotbed) and then it eventually floats in the air and does a little dance for me. I took a video if you are interested, it is on youtube at http://youtu.be/2p0GpT4zU6c

Now this is better than before where it used to bash the extruders on anything it could find.

You may also notice that my Z probe is very long now, well I quickly made a replacement for a number of reasons, but primarily becasue the old one is the same length as the extruders and it basically would be very difficult to get it to work reliably for this testing phase.

I have logged a message with technical support, I think that it is about time I got them providing suggestions on this as I have been playing around all week now.

[moriartynz]

Hi Rickr,

The M119 command will not cause the printer itself to do anything. Rather, it should output the status of the endstops in your terminal window in Repetier's serial console.

I had a similar issue with my printer initially and it was because the motor travel direction was incorrect. See this thread: http://www.geeetech.com/forum/viewtopic ... 20&t=16793
When the printer is homed, it needs to be travelling upwards towards the endstops (away from the bed). The configuration file needed the following changes:
#define INVERT_X_DIR true // for Mendel set to false, for Orca set to true
#define INVERT_Y_DIR true // for Mendel set to true, for Orca set to false
#define INVERT_Z_DIR true // for Mendel set to false, for Orca set to true

Regards
Mark