D3D Automatic Bed Leveling - Revision history

Marcin: /* Test Procedure Logic */

2017-06-19T16:22:44Z

Test Procedure Logic

← Older revision		Revision as of 16:22, 19 June 2017
Line 86:		Line 86:
	#Move down to get offset.		#Move down to get offset.
	#Set offset. M851 Z10 and M206 Z10. See if new G1 Z0 zero goes to ~10 mm above bed?		#Set offset. M851 Z10 and M206 Z10. See if new G1 Z0 zero goes to ~10 mm above bed?

			=Communications=
			To Chris Palmer and Bernhard Kubicek, Marlin developers:

			Hi Chris and Bernhard,

			I saw your dev thread at https://github.com/MarlinFirmware/Marlin/issues/1244 - and I would like to ask regarding the latest status of Marlin auto bed leveling. Is nonlinear (bed warp-correcting) bed leveling implemented?

			I am still not clear after that thread whether nonlinear bed correction is implemented (correction for bed warping - does not assume a perfectly flat bed surface) or does Marlin only have a linear bed tilt correction (assumes a perfectly flat but tilted bed).

			I have tried to get mesh leveling to work with both 2x2 and 3x3 grids and couldn't get it to work accurately enough. I checked different aluminum print surfaces, and still no good. The following of the bed with air printing was off by up to 2 mm over a 6" area. So I switched to 3-point leveling, and that works fine, to about +/- 0.1 mm over a typical print. I am using Marlin 1.1.0-RC8 - 6 Dec 2016 from the main Github repository.

			We are developing a 1'x4' print bed printer - and the nonlinear correction feature would be indispensable to keep bed costs down by allowing use of non-precision metal surfaces. You can see our work on the 3D printer at on the open source ecology wiki.

			Marcin

Marcin: /* Useful Links */

2017-06-18T00:28:58Z

Useful Links

← Older revision		Revision as of 00:28, 18 June 2017
Line 51:		Line 51:

	=Useful Links=		=Useful Links=
	*Good discussion with Marlin heavyweights - [https://github.com/MarlinFirmware/Marlin/issues/1244]		*Good discussion with Marlin heavyweights - [https://github.com/MarlinFirmware/Marlin/issues/1244]. Bernhardt Kubicek (lastname at gmx.at)
	*Actual explanation, but for manual bed level - [https://airtripper.com/1799/marlin-firmware-home-offset-guide-using-g-code-m206/]		*Actual explanation, but for manual bed level - [https://airtripper.com/1799/marlin-firmware-home-offset-guide-using-g-code-m206/]
	*Verbose G29 - [https://www.reddit.com/r/3Dprinting/comments/460wfx/help_decoding_g29_auto_bed_leveling_output/]		*Verbose G29 - [https://www.reddit.com/r/3Dprinting/comments/460wfx/help_decoding_g29_auto_bed_leveling_output/]

Marcin: /* Useful Links */

2017-06-18T00:28:10Z

Useful Links

← Older revision		Revision as of 00:28, 18 June 2017
Line 51:		Line 51:

	=Useful Links=		=Useful Links=
			*Good discussion with Marlin heavyweights - [https://github.com/MarlinFirmware/Marlin/issues/1244]
	*Actual explanation, but for manual bed level - [https://airtripper.com/1799/marlin-firmware-home-offset-guide-using-g-code-m206/]		*Actual explanation, but for manual bed level - [https://airtripper.com/1799/marlin-firmware-home-offset-guide-using-g-code-m206/]
	*Verbose G29 - [https://www.reddit.com/r/3Dprinting/comments/460wfx/help_decoding_g29_auto_bed_leveling_output/]		*Verbose G29 - [https://www.reddit.com/r/3Dprinting/comments/460wfx/help_decoding_g29_auto_bed_leveling_output/]

Marcin: /* Test Procedure Logic */

2017-06-17T02:51:24Z

Test Procedure Logic

← Older revision		Revision as of 02:51, 17 June 2017
Line 77:		Line 77:
	#Move to mid of bed. G1 Xmid Ymid.		#Move to mid of bed. G1 Xmid Ymid.
	#Record height above bed. It should not be at zero there - it could either be below (crash) or above. The software endstops should be disabled in firmware - so should definitely be able to crash into bed, so be careful.		#Record height above bed. It should not be at zero there - it could either be below (crash) or above. The software endstops should be disabled in firmware - so should definitely be able to crash into bed, so be careful.
			#Shift the z offset. Does that do anything with M851 Z10? What happens with G1 Z0? Nothing, as the offset is only an automatic bed level feature?
	#Auto bed level G29		#Auto bed level G29
	#Move to mid of bed. G1 Xmid Ymid.		#Move to mid of bed. G1 Xmid Ymid.

Marcin: /* Test Procedure Logic */

2017-06-17T02:48:16Z

Test Procedure Logic

← Older revision		Revision as of 02:48, 17 June 2017
Line 77:		Line 77:
	#Move to mid of bed. G1 Xmid Ymid.		#Move to mid of bed. G1 Xmid Ymid.
	#Record height above bed. It should not be at zero there - it could either be below (crash) or above. The software endstops should be disabled in firmware - so should definitely be able to crash into bed, so be careful.		#Record height above bed. It should not be at zero there - it could either be below (crash) or above. The software endstops should be disabled in firmware - so should definitely be able to crash into bed, so be careful.
	#Try a g-code print file here. No start g-code involved in that case. See if we can print a simple file - such as a square around the middle. Create a test STL. Run it. Export the Gcode - read it to see if it's usable.
	#Auto bed level G29		#Auto bed level G29
	#Move to mid of bed. G1 Xmid Ymid.		#Move to mid of bed. G1 Xmid Ymid.
Line 84:		Line 84:
	#G92 Z10		#G92 Z10
	#Move down to get offset.		#Move down to get offset.
	#Im		#Set offset. M851 Z10 and M206 Z10. See if new G1 Z0 zero goes to ~10 mm above bed?

Marcin: /* Test Procedure Logic */

2017-06-17T02:43:52Z

Test Procedure Logic

← Older revision		Revision as of 02:43, 17 June 2017
Line 77:		Line 77:
	#Move to mid of bed. G1 Xmid Ymid.		#Move to mid of bed. G1 Xmid Ymid.
	#Record height above bed. It should not be at zero there - it could either be below (crash) or above. The software endstops should be disabled in firmware - so should definitely be able to crash into bed, so be careful.		#Record height above bed. It should not be at zero there - it could either be below (crash) or above. The software endstops should be disabled in firmware - so should definitely be able to crash into bed, so be careful.
	#		#Try a g-code print file here. No start g-code involved in that case. See if we can print a simple file - such as a square around the middle. Create a test STL. Run it. Export the Gcode - read it to see if it's usable.
	#Auto bed level G29		#Auto bed level G29
	#Move to mid of bed. G1 Xmid Ymid.		#Move to mid of bed. G1 Xmid Ymid.

Marcin: /* Useful Links */

2017-06-17T01:49:31Z

Useful Links

← Older revision		Revision as of 01:49, 17 June 2017
Line 52:		Line 52:
	=Useful Links=		=Useful Links=
	*Actual explanation, but for manual bed level - [https://airtripper.com/1799/marlin-firmware-home-offset-guide-using-g-code-m206/]		*Actual explanation, but for manual bed level - [https://airtripper.com/1799/marlin-firmware-home-offset-guide-using-g-code-m206/]
			*Verbose G29 - [https://www.reddit.com/r/3Dprinting/comments/460wfx/help_decoding_g29_auto_bed_leveling_output/]

	=Test Procedure Logic=		=Test Procedure Logic=

Marcin: /* Test Procedure Logic */

2017-06-17T01:39:45Z

Test Procedure Logic

← Older revision		Revision as of 01:39, 17 June 2017
Line 70:		Line 70:
	Say we move to the middle of the print bed. We measure the offset there:		Say we move to the middle of the print bed. We measure the offset there:

	#Reflash firmware to speed up testing process. Faster speed between probing		#Reflash firmware to speed up testing process. Faster speed between probing. Turn of bed heat to make that faster.
	Move manually to mid of bed, note location.		#Move manually to mid of bed, note location.
	#Zero all axes G28		#Zero all axes G28.
			#Move to 0 height location. Record height above bed. Should be zero. Raise head to allow motion to mid of bed.
			#Move to mid of bed. G1 Xmid Ymid.
			#Record height above bed. It should not be at zero there - it could either be below (crash) or above. The software endstops should be disabled in firmware - so should definitely be able to crash into bed, so be careful.
			#
	#Auto bed level G29		#Auto bed level G29
	#Move to mid of bed. Note ~~tha~~		#Move to mid of bed. G1 Xmid Ymid.
			#Move to 0 height location. G1 Z0. Note the location above bed.
	#Move down until triggered		#Move down until triggered
	#G92 Z10		#G92 Z10
	#Move down to get offset.		#Move down to get offset.
	#Im		#Im

Marcin: /* Test Procedure Logic */

2017-06-17T01:03:47Z

Test Procedure Logic

← Older revision		Revision as of 01:03, 17 June 2017
Line 64:		Line 64:
	To know that everything is happening as it should, we should test manually first.		To know that everything is happening as it should, we should test manually first.

	Do G29. Then move the print head to zero height. The height should end up .1mm above bed.		Do G29. Then move the print head to zero height. The height should end up .1mm above bed ideally, but in reality, it will have an offset.

	~~If not, is~~ there a command that can override the head height? That should be the G92. With software endstops deactivated, setting G92 Z1 should allow movement down to zero. G1 Z0 should move the Z axis down by 1 if the axis were homed at Z=1. This means we artificially insert an offset. We can find that offset at any position on the print bed.		Is there a command that can override the head height? That should be the G92. With software endstops deactivated, setting G92 Z1 should allow movement down to zero. G1 Z0 should move the Z axis down by 1 if the axis were homed at Z=1. This means we artificially insert an offset. We can find that offset at any position on the print bed.

	Say we move to the middle of the print bed. We measure the offset there:		Say we move to the middle of the print bed. We measure the offset there:

	#Move to mid of bed.		#Reflash firmware to speed up testing process. Faster speed between probing
			Move manually to mid of bed, note location.
			#Zero all axes G28
			#Auto bed level G29
			#Move to mid of bed. Note tha
	#Move down until triggered		#Move down until triggered
	#		#G92 Z10
			#Move down to get offset.
			#Im

Marcin: /* Test Procedure Logic */

2017-06-16T22:59:37Z

Test Procedure Logic

← Older revision		Revision as of 22:59, 16 June 2017
Line 67:		Line 67:

	If not, is there a command that can override the head height? That should be the G92. With software endstops deactivated, setting G92 Z1 should allow movement down to zero. G1 Z0 should move the Z axis down by 1 if the axis were homed at Z=1. This means we artificially insert an offset. We can find that offset at any position on the print bed.		If not, is there a command that can override the head height? That should be the G92. With software endstops deactivated, setting G92 Z1 should allow movement down to zero. G1 Z0 should move the Z axis down by 1 if the axis were homed at Z=1. This means we artificially insert an offset. We can find that offset at any position on the print bed.

			Say we move to the middle of the print bed. We measure the offset there:

			#Move to mid of bed.
			#Move down until triggered
			#