Bed Auto Leveling.. check this out

Thanks, I will work on that idea.

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

I got it going i just went to a different computer and used fresh firmware from both sites and it works

I appreciate the help Thank You very much

Another question prusa i3v i got the auto bed leveling working but its doing the grid, how do i get it to do just 3 points instead of 4 my bed is 8inch by 12 inches i attached the configuration.h file

Quote
Draob
Some printers who have a metal bed use a magnetic sensor directly on the carriage and get the same results with +/- .05 precision everytime.

Would a Hall effect sensor be able to detect a magnetic field generated by the current in the heatbed (if there is one)?

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

Quote
AbuMaia

Quote
Draob
Some printers who have a metal bed use a magnetic sensor directly on the carriage and get the same results with +/- .05 precision everytime.

Would a Hall effect sensor be able to detect a magnetic field generated by the current in the heatbed (if there is one)?

My guess is No, because the magnetic field would not be exactly the same in different places on the bed. These devises are very accurate and would need to have exactly the same magnetic field power at each place that is probed.

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

I changed some details at my printer and had to set the numbers in Marlin again, but now my printer goes after the probing (G29) to the maximum of the X-Axis and beyond if I don't turn it off.
I googled a lot but didn't find anything similar. Does someone had some problem like that?
Why does it even move at all after the G29?
Everything else works fine, it's just went suicidal after the G29 for some reasons...

I just installed the new Marlin again and it works now...

Quote
intosite


What value disc capacitor should i try?

When using a LM78XX (LM7805, LM7812, etc), the minimum circuit is given in Figure 8 of the datasheet. Which says to use a 0.33 μF or larger tantalum, mylar or other capacitor having low internal impedance" (pg 25) between pins 1-2 and a 0.1uF between points 2-3. The datasheet did not specify what type of capcitor to use for the 0.1uF. But, I think I recall this being a ceramic type.

To test a servo with a Servo Tester, plug the servo into your board as you normally would and use the Arduino IDE to upload the standard Servo Sweep (see attached). Just ensure that you change myservo.attach(11) to the appropiate pin for your board. This sketch will sweep the servo from 0-180 degrees.

I've been trying to get AB working on my Makerfarm i3v 10" for a few days and am running in to this error when I try to verify:

Marlin_main.cpp: In function 'void dock_sled(bool, int)':
Marlin_main.cpp:1289: error: 'SLED_DOCKING_OFFSET' was not declared in this scope
Marlin_main.cpp:1299: error: 'SLED_DOCKING_OFFSET' was not declared in this scope

The only changes I've made is to the configuration.h file, so I'm not really sure where to go from here. Do I need a different main.cpp? Any help would be appreciated. I have attached the configuration.h and I'm running arduino 1.0.5-R2

In configuration.h find SLED_DOCKING_OFFSET and remove the // in front. I also changed it to zero. It compiles fine now.

Looks like they forgot add a ifdef for the dock_sled function if you're not using a z sled.

Is there a discussion somewhere about which type of switch is best to use for ABL? Or do we just use whatever is handy? I ask because I feel I could make my Z probe more compact if I use either a momentary tactile switch or a momentary pushbutton switch instead of the microswitch everyone seems to use because it was their old Z limit switch.

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

I'm a little confused on setting the offset. I understand the tutorials say take the nozzle and touch the bed, then back it off so you have the clearance of a sheet of paper, just like you would do if you did it manually. Lets say it's .1mm thick. Then set that as X0 Y0 Z0 and then put the probe/microswitch down on that same spot till it triggers. Effectively setting it so that when you G29, the bed is probed, and when you print Z0 is supposed to be at .1mm, but my question comes in with Slic3r. Looking at the gcode, it looks like it actually puts the first layer down at a height at which it's told to. In my example .35 but as the tutorials tell us to set the offset, that's technically .45 and my layers aren't sticking. Is my thought right on that?

Quote
FA-MAS
I'm a little confused on setting the offset. I understand the tutorials say take the nozzle and touch the bed, then back it off so you have the clearance of a sheet of paper, just like you would do if you did it manually. Lets say it's .1mm thick. Then set that as X0 Y0 Z0 and then put the probe/microswitch down on that same spot till it triggers. Effectively setting it so that when you G29, the bed is probed, and when you print Z0 is supposed to be at .1mm, but my question comes in with Slic3r. Looking at the gcode, it looks like it actually puts the first layer down at a height at which it's told to. In my example .35 but as the tutorials tell us to set the offset, that's technically .45 and my layers aren't sticking. Is my thought right on that?

Using this method is so easy and very accurate too.
Just one variable to change in the firmware and then the rest is done automatically.
1. Home the Z. It will be above the bed but will read as zero position.
2. Lower nozzle to bed position. Use paper to get the correct bed space.
3. Send M114 from Pronterface to read the position.
4. The reading shown on the screen will be the exact value to put in the firmware for the offset.
5. Program the board as usual.
Takes just a couple of minutes beginning to end and can be checked at anytime and changed if anything moves out of kilter So Easy.

// ENDSTOP SETTINGS:
// Sets direction of endstops when homing; 1=MAX, -1=MIN
#define X_HOME_DIR -1
#define Y_HOME_DIR -1
#define Z_HOME_DIR -1

#define min_software_endstops false // If true, axis won't move to coordinates less than HOME_POS.
#define max_software_endstops true // If true, axis won't move to coordinates greater than the defined lengths below.

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

I've got the offset right with that method. I'm saying that if you look at the gcode, slic3r moves the nozzle up the distance set as the 1st layer in the settings (G0 Z0.35 in my example) from where the autolevel measured Z0 thus making it's true height off the bed Z0.45 and then the layer's not squished enough.

Quote
FA-MAS
I've got the offset right with that method. I'm saying that if you look at the gcode, slic3r moves the nozzle up the distance set as the 1st layer in the settings (G0 Z0.35 in my example) from where the autolevel measured Z0 thus making it's true height off the bed Z0.45 and then the layer's not squished enough.

Change the setting in the g-code.

I am using Cura and this is what I have in my start code;

;Print time: {print_time}
;Filament used: {filament_amount}m {filament_weight}g
;Filament cost: {filament_cost}
;M190 S{print_bed_temperature} ;Uncomment to add your own bed temperature line
;M109 S{print_temperature} ;Uncomment to add your own temperature line
G21 ;metric values
G90 ;absolute positioning
M107 ;start with the fan off
G92 ;zero all axis
G1 Z20.0 F{travel_speed} ;move the nozzle up 20mm
G28 ;home all axis
G29 ;auto bed leveling probes
G92 E0 ;reset extruder
M82 ;set extruder mode
G1 Z5 ;move nozzle up 5mm so it clears the bed while moving
G1 X5 Y5 ;almost home X and Y axis
G1 Z0.5 ;move nozzle to print height, drop nozzle down near the bed
G1 E40 X90 F700 ;extrude some filament in a short line to prime the nozzle.
G92 E0 ;zero the extruded length again
G1 F{travel_speed}
;Put printing message on LCD screen
M117 Printing...

Edited 1 time(s). Last edit at 09/10/2014 07:21PM by regpye.

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Quote
regpye
Using this method is so easy and very accurate too.
Just one variable to change in the firmware and then the rest is done automatically.
1. Home the Z. It will be above the bed but will read as zero position.
2. Lower nozzle to bed position. Use paper to get the correct bed space.
3. Send M114 from Pronterface to read the position.
4. The reading shown on the screen will be the exact value to put in the firmware for the offset.
5. Program the board as usual.
Takes just a couple of minutes beginning to end and can be checked at anytime and changed if anything moves out of kilter So Easy.

Well this is weird. If I use your method, I get a Z offset of -4.1. If I use ZennMasterZ's method of starting from the extruder a paper's thickness off the glass, set position to 0, then adjust until the probe switch clicks, I get a Z offset of -10.8. What's going on? Which number should I use?

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

Quote
AbuMaia

Quote
regpye
Using this method is so easy and very accurate too.
Just one variable to change in the firmware and then the rest is done automatically.
1. Home the Z. It will be above the bed but will read as zero position.
2. Lower nozzle to bed position. Use paper to get the correct bed space.
3. Send M114 from Pronterface to read the position.
4. The reading shown on the screen will be the exact value to put in the firmware for the offset.
5. Program the board as usual.
Takes just a couple of minutes beginning to end and can be checked at anytime and changed if anything moves out of kilter So Easy.

Well this is weird. If I use your method, I get a Z offset of -4.1. If I use ZennMasterZ's method of starting from the extruder a paper's thickness off the glass, set position to 0, then adjust until the probe switch clicks, I get a Z offset of -10.8. What's going on? Which number should I use?

If you want to do it the hard way, keep doing as you have been.
My method works every time and is very easy. Not had a failure yet and I have setup many this way.

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Quote
regpye
If you want to do it the hard way, keep doing as you have been.
My method works every time and is very easy. Not had a failure yet and I have setup many this way.

Do you get as big a variation in numbers when you do it both ways?

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

Quote
AbuMaia

Quote
regpye
If you want to do it the hard way, keep doing as you have been.
My method works every time and is very easy. Not had a failure yet and I have setup many this way.

Do you get as big a variation in numbers when you do it both ways?

I have only done the one way.

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Quote
FA-MAS
I've got the offset right with that method. I'm saying that if you look at the gcode, slic3r moves the nozzle up the distance set as the 1st layer in the settings (G0 Z0.35 in my example) from where the autolevel measured Z0 thus making it's true height off the bed Z0.45 and then the layer's not squished enough.

After you figured out your z offset, put that in your firmware and flashed it, did you do the EEPROM command to restore settings from the firmware (M502), then save them back to EEPROM (M500)? If you don't do that, the z offset will not be saved to EEPROM and your nozzle will be that offset off from where it should be. Using Zennmaster's or Regpye's method should give you the very close to the same offset (though Zennmaster's will need to have the sign flipped). You are just doing things in reverse. Zennmaster says to start at .1mm off the bed, then raise the nozzle to the place that will be your new home position with the probe. Regpye, just starts with the probe triggered, then moves down to .1mm. If you are seeing something really different like you are, then something is not being done quite right.

Edited 2 time(s). Last edit at 09/11/2014 01:05AM by brucehvn.

Quote
regpye

Quote
AbuMaia

Quote
regpye
If you want to do it the hard way, keep doing as you have been.
My method works every time and is very easy. Not had a failure yet and I have setup many this way.

Do you get as big a variation in numbers when you do it both ways?

I have only done the one way.

Very well. I'm glad your way works for you. Perhaps someone else may be more helpful.

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

I've got my ABL working now and there's just one final detail I need help with. After any operation that uses the servo (G28 or G29), how do I have the Z axis raise a bit before servo retract? Right now the micro switch is very slightly hitting the bed when the final retract is issued. Any ideas?

Check here: [3dprintboard.com]

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

Quote
AbuMaia
Check here: [3dprintboard.com]

Thanks for the link. I'll check it out.

For anyone interested, I do 5-point bed levelling (4 corner points + centre of the bed) using a differential IR sensor that I have developed and Duet hardware. The sensor uses two modulated infrared beams and picks up their reflections from the bed, inspired by height sensing method used on the Dambusters raid. I have manufactured two batches of these boards for other 3D printer owners. Most of them use the board on Ormerods but at least one uses it on a Mendel. I have some boards left from the second batch. See [miscsolutions.wordpress.com] for more informaton about the board and [forums.reprap.org] for ordering details.



Does anyone have any software or just the basic algorithm for using more than 5 probe points? The 5 point compensation works fairly well, but on the Ormerod at least I think 9 point compensation would work better.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
dc42
For anyone interested, I do 5-point bed levelling (4 corner points + centre of the bed) using a differential IR sensor that I have developed and Duet hardware. The sensor uses two modulated infrared beams and picks up their reflections from the bed, inspired by height sensing method used on the Dambusters raid. I have manufactured two batches of these boards for other 3D printer owners. Most of them use the board on Ormerods but at least one uses it on a Mendel. I have some boards left from the second batch. See [miscsolutions.wordpress.com] for more informaton about the board and [forums.reprap.org] for ordering details.

2014-06-19%2014.16.36.jpg

Does anyone have any software or just the basic algorithm for using more than 5 probe points? The 5 point compensation works fairly well, but on the Ormerod at least I think 9 point compensation would work better.

Go here for the latest in this area.
I believe the last time I checked there was 16 points available or even more.

[3dprintboard.com]

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[regpye.com.au]
"Experience is the mother of all knowledge." --Leonardo da Vinci

Yes, good link. I use the Enhanced G29 from there, and have a 16-point bed level check before every print, and a 25-point check for bed topography.

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MakerFarm 8" Prusa i3v
RAMPS 1.4
0.4mm E3D v6 for 1.75mm

Hi there!

I have a problem with my auto bed leveling.
My config is RAMPS1.4, marlin fw, a servo arm, probe sw on z min home.
My servo is working, responding to any command.

My problem is that when I issue a G28 (home), x, y axes are homing, then Z as usually. Just before Z starts homing it will activate the servo and lovers the arm, once the homing is done it will never retract the servo arm.
When Issuing G29 (auto probe and leveling) servo is lovering the arm and it will retract once de process completes.

I found out that it may have something to do with "#define PROBE_SERVO_DEACTIVATION_DELAY 300" option. If this is enabled servo is not retracting after homing
If the above option is commented out my servo arm is retracting as it should but unfortunately with option commented out I have servo jerk which is unacceptable.

Does anyone have an idea what I'm doing wrong?

Thanks!

I'm seeing the same issue too. I'm curious about a fix also. In my starting gcode, I added a lift to 5mm, then M402. It then resumes it's normal routine. No problems printing, just a slight annoyance I'd like to see fixed.

Edited 1 time(s). Last edit at 09/16/2014 03:31PM by FA-MAS.

It's happening to me also. For now, I'm adding a M402 after the G28.

Edited 1 time(s). Last edit at 09/16/2014 03:03PM by stephenrc.